Firefox... taming the beast part 2 !!

 For those who want the Firefox of yesteryear, or something in between, we have solutions...

 The next step would be a few about:config edits.

Open a new tab and type about:config in the address bar.
Answer that yes, you will be cautious.
To find these settings, just copy/paste a setting name in the search box.
Double clicking a setting will toggle it to true or false.

toolkit.legacyUserProfileCustomizations.stylesheets = True <--- Tells Firefox to read a .css file we will add.
svg.context-properties.content.enabled = False <---- also needed
browser.compactmode.show = True
browser.toolbars.keyboard_navigation = False <---- (undo the new keyboard navigation in FF 103)

browser.proton.contextmenus.enabled = False (bookmarks spacing) <---- (might want to play around with this)
browser.proton.enabled = True <--- (since FF 91.0)
browser.proton.places-tooltip.enabled = False
browser.proton.toolbar.version = 3

browser.aboutwelcome.design = False
widget.non-native-theme.scrollbar.style = 0 <--- (set W11 scrollbar width back to normal width (range 0-5))

reader.parse-on-load.enabled = False (removes little blue page icon at right end of address bar)
browser.newtabpage.activity-stream.improvesearch.handoffToAwesomebar = False <---- New tab search stays as a search (doesn't redirect to address bar)
browser.tabs.tabmanager.enabled = False <----- Hides Firefox's new "List all tabs icon".
extensions.unifiedExtensions.enabled = False <----- Hides the puzzle piece icon (extensions icon), at far right, before FF 110.0

And these are just old about:config settings, from long before FF 89
Set all these to False...

browser.shell.checkDefaultBrowser

browser.urlbar.openViewOnFocus
browser.urlbar.update1
browser.urlbar.update1.interventions
browser.urlbar.update1.searchTips
browser.urlbar.update1.view.stripHttps




And these are just odd little tweaks...

browser.urlbar.groupLabels.enabled = False <---- disables Firefox Suggest (FF 92 and later)
browser.download.improvements_to_download_panel = False <---- brings back the Firefox download dialog
toolkit.zoomManager.zoomValues .3,.5,.67,.8,.9,1,1.1,1.2,1.33,1.5,1.7,2,2.4,3,4,5 <---- values for the Zoom button
contextualSearch.enabled = True <----- enables site-specific Search (coming soon, on Nightly, now)

 Close Firefox and put this Chrome folder (unzipped ofc), in place of the current one, in...

The "Chrome" folder and it's userChrome.css file allows even more tweaks.
These links are for the Chrome folder I use, that allows you to just turn ON or turn OFF, various things.
You can also make a Chrome folder/userChrome.css file of your own, if desired.

INFO: userChrome.css for Customizing Firefox

Chrome 4.3.4.zip <---- latest
Chrome 4.20.zip
Chrome 4.13.zip


C:\Users\xxxxx\AppData\Roaming\Mozilla\Firefox\Profiles\xxxxxxx.default-release

Then restart Firefox.
Any other adjustments to the looks of Firefox were done via Tools > Settings or the Customize page.

Unedited Chrome folder: Latest Chrome folder at... GitHub


Links for the more energetic...

Resources for Style Recipes and Tools


UPDATE for Firefox 99.0 bookmarks spacing...

Firefox... taming the beast part 2 !!




UPDATE For adding scroll bar to Bookmarks Menu...

Firefox... taming the beast part 2 !!





Bottom left of the Firefox Customize page...




Firefox address bar about: commands... Complete List Of Firefox About: Commands

Don't understand why you needed a "Part 2" Ghot ....Think your original thread was working just fine....

qbdp said:

Thank you very much for all who participated in the part 1, and especially the thread starter Ghot, very educational and practical, much appreciated.
Is there a site or two where I can copy/paste codes as needed?
Codes in png format are not practical for me, am sure it is possible to convert to text however my attempts are all converted wrong.
Regards,

That .png image is just for an example. The "code" is all in the Chrome.7z download or the GitHub link.
The userChrome.css file where all the code is... is fairly large, so I didn't post the code in the thread.


But since I won't be editing THIS post... here's the code...

Version 4.0.0

Code:

/* Firefox userChrome.css tweaks ****************************************************************/
/* code mostly taken from 'Classic Theme Restorer' & 'Classic Toolbar Buttons' add-ons **********/
/* Github: https://github.com/aris-t2/customcssforfx ********************************************/
/************************************************************************************************/

/************************************************************************************************/
/* Custom CSS for Firefox 91+ *******************************************************************/
/* version 4.0.0 ********************************************************************************/
/************************************************************************************************/

/*************************************************************************************************

 Full changelog of every version: https://github.com/Aris-t2/CustomCSSforFx/commits/
  
 [!] Firefox requires this preference to be enabled or custom styles will not be loaded:
	 'about:config > toolkit.legacyUserProfileCustomizations.stylesheets > true'

*************************************************************************************************/

/*************************************************************************************************

  README
  
  Finding profile folder: address bar > about:support > Profile Folder > Open Folder
  CSS files and sub-folders belong into \PROFILEFOLDER\chrome\ directory.
  \chrome\config\
  \chrome\css\
  \chrome\image\
  \chrome\userChrome.css
  \chrome\userContent.css

  ENABLING options: remove the combination of / and * in front of '@import'
  DISABLING options: add the combination of / and * in front of '@import'

  macOS issues / glitches / fixes -> look for 'macOS fix' additions inside this file
  - tabs toolbar spaces in 'toolbars' category
  - tabs not on top mode in 'tabs toolbar position' category
  - page context items in 'general ui' category

  EXPERIMENTAL settings are for testing only!
  
  BASIC OVERVIEW - settings this file contains:
  CONFIGURATION FILES
  - general variables / color variables (default browser theme only)
  TOOLBAR BUTTONS
  - toolbar button / icon appearance
  - bookmarks menu button / popup
  - other button settings
  - custom BACK and FORWARD buttons appearance
  - APPLICATION/HAMBURGER BUTTON
  -- visibility / popup
  -- buttons appearance on navigation toolbar / in Firefox titlebar
  TABS
  - custom tab appearance / old squared tabs
  - TABS TOOLBAR POSITION
  -- below titlebar / navigation and bookmarks toolbar / main content
  - TAB TEXT - colors/shadow/weight/style for default/active/hovered/unloaded tabs
  - MULTIROW / multi lined tabs
  - TAB TITLE IN FIREFOX TITLEBAR
  - empty tab favicon / custom tab loading animation / tab close icon settings
  - settings for DEFAULT TABS / other tab settings
  GENERAL UI
  - general settings / close icons / page context menu items
  - overflow menu / sidebar / findbar
  - SEARCHBAR
  -- general settings for default search
  -- OLD SEARCH + old search 'about:config' settings
  - MENUBARS bookmarks menu popup items
  TOOLBARS
  - ADDONS BAR (simulated bottoms toolbar)
  - GENERAL TOOLBAR settings
  -- toolbar context menu settings
  - MENUBAR settings
  - bookmarks toolbar settings
  - BOOKMARKS TOOLBAR - MULTIPLE LINES
  - AeroGlass TOOLBARS / WIN10 fix for GLASS8
  - TOOLBAR TEXT MODES
  -- icons+text / text only
  LOCATION BAR / urlbar / awesomebar
  - general location bar tweaks / identity box / padlock icons icon/button tweaks
  - 'autocomplete popup' appearance / result item settings/appearance


*************************************************************************************************/

/************************************************************************************************/
/* CONFIGURATION FILES - edit target files to change general values *****************************/
/************************************************************************************************/

/* GENERAL VARIABLES ****************************************************************************/
/* [!] set global variables for font and tab size options and more inside target file ***********/
@import "./config/general_variables.css"; /**/

/* COLOR VARIABLES FOR DEFAULT BROWSER THEME ONLY - MAIN UI - [only use one at a time] **********/
/* [!] set own colors for tabs & toolbars inside 'color_variables.css' or use available presets */
/* [!] enabled 'menubar_color.css' and 'statusbar_color.css' might be required in some cases ****/
/* @import "./config/color_variables.css"; /**/  /* <- default 'grey' colors */
/* @import "./config/color_variables_aero.css"; /**/  /* <- 'AeroBlue' colors (Win 7 Aero) */
@import "./config/color_variables_classic-grey.css"; /**/  /* <- 'classic grey' colors (Win Classic) */
/* @import "./config/color_variables_fx3.css"; /**/  /* <- 'Firefox 3-like' blueish colors */
/* @import "./config/color_variables_transparent.css"; /**/  /* <- (semi-)'transparent' colors */
/* @import "./config/color_variables_aeroglass.css"; /**/  /* <- 'AeroGlass' colors / Win10+Glass8 fix can be found in 'toolbars' area */
/* @import "./config/color_variables_deved.css"; /**/  /* <- based on 'Developer Edition' colors */
/* @import "./config/color_variables_noia4_grey.css"; /**/  /* <- based on 'Noia 4 themes' grey colors */
/* @import "./config/color_variables_noia4_lightgrey.css"; /**/  /* <- based on 'Noia 4 themes' lightgrey colors */
/* @import "./config/color_variables_noia4_dark.css"; /**/  /* <- based on 'Noia 4 themes' dark colors */

/* Darker "Dark" default theme - [only use one at a time] ***************************************/
/* @import "./css/toolbars/default_dark_theme_darker.css"; /**/
/* @import "./css/toolbars/default_dark_theme_darker_v2.css"; /**/

/* CUSTOM SCROLLBARS VARIABLES - EXPERIMENTAL ***************************************************/
/* [!] Might not work on every page! This issue is for Mozilla to solve. ************************/
/* [!] Not compatible with custom scrollbar JavaScript userChrome scripts. **********************/
/* [!] Custom size values only compatible with 'web content' scrollbars at the moment. **********/
/* [!] More info inside 'custom_scrollbar_appearance.css' file. *********************************/
/* @import "./config/custom_scrollbar_appearance.css"; /**/		/* <--- EXPERIMENTAL */


/************************************************************************************************/
/* TOOLBAR BUTTONS ******************************************************************************/
/************************************************************************************************/

/* icon appearance - [only use one at a time] (custom icons do not scale in HiDPI modes) ********/
/* @import "./css/buttons/icons_colorized.css"; /**/
/* @import "./css/buttons/icons_white_icons.css"; /**/
/* @import "./css/buttons/icons_custom_icons.css"; /**/  /* aka "Mozilla Mix" from CTB */
/* @import "./css/buttons/icons_custom_icons_fx1.css"; /**/
/* @import "./css/buttons/icons_custom_icons_fx2.css"; /**/
/* @import "./css/buttons/icons_custom_icons_fx3.css"; /**/
/* @import "./css/buttons/icons_custom_icons_fx3strata.css"; /**/
/* @import "./css/buttons/icons_custom_icons_fx12_colorized.css"; /**/
/* @import "./css/buttons/icons_custom_icons_crystal.css"; /**/
/* @import "./css/buttons/icons_custom_icons_firebird.css"; /**/
/* @import "./css/buttons/icons_custom_icons_kempelton.css"; /**/
/* @import "./css/buttons/icons_custom_icons_noia.css"; /**/
/* @import "./css/buttons/icons_custom_icons_ie6.css"; /**/
/* @import "./css/buttons/icons_custom_icons_seamonkey.css"; /**/
/* @import "./css/buttons/icons_custom_icons_old_chrome.css"; /**/
/* @import "./css/buttons/icons_custom_icons_old_osx.css"; /**/
/* @import "./css/buttons/icons_custom_icons_tango.css"; /**/
@import "./css/buttons/icons_custom_icons_fx45.css"; /**/
/* @import "./css/buttons/icons_custom_icons_fx45_inverted.css"; /**/


/* PROTON: 'classic' pre-Proton button padding **************************************************/
/* @import "./css/buttons/classic_button_padding.css"; /**/

/* navigation toolbar buttons appearance - [only use one at a time] *****************************/
/* @import "./css/buttons/buttons_on_navbar_classic_appearance.css"; /**/
@import "./css/buttons/buttons_on_navbar_classic_appearance_v2.css"; /**/
/* @import "./css/buttons/buttons_on_navbar_windows_classic_theme_appearance.css"; /**/
/* @import "./css/buttons/buttons_on_navbar_glass_appearance.css";			/* <--- good for Dark themes */
/* @import "./css/buttons/buttons_on_navbar_osx_appearance.css"; /**/

/* navigation toolbar buttons - button roundness (edit file to set different roundness) *********/
/* @import "./css/buttons/buttons_on_navbar_button_roundness.css"; /**/

/* squared buttons / button size - [only use one at a time] *************************************/
/* "rectangular shape" - normal size ************************************************************/
/* @import "./css/buttons/buttons_on_navbar_squared_buttons.css"; /**/
/* "normal shape" - large size (huge 48x48px buttons with 36x36px icons) ************************/
/* [!] not compatible with 'custom icon' options ************************************************/
/* [!] not compatible with 'custom back & forward buttons' appearance options *******************/
/* [!] not compatible with 'text mode' option ***************************************************/
/* [!] partly compatible with 'icons+text' option, if in 'compact mode' *************************/
/* @import "./css/buttons/buttons_on_navbar_huge_48px_size.css"; /**/			/* <--- EXPERIMENTAL */

/* smaller button spaces in 'compact' mode - 'Classic Toolbar Buttons' add-ons 'small' mode *****/
/* @import "./css/buttons/buttons_on_navbar_more_compact_mode.css"; /**/

/* bookmarks toolbar - buttons appearance - [only use one at a time] ****************************/
/* old bookmarks toolbar button appearance ******************************************************/
@import "./css/buttons/buttons_on_bookmarks_toolbar_old_size_and_appearance.css"; /**/  /* Windows only */
/* @import "./css/buttons/buttons_on_bookmarks_toolbar_classic_appearance.css"; /**/
/* @import "./css/buttons/buttons_on_bookmarks_toolbar_classic_appearance_items.css"; /**/

/* menubar - toolbar button appearance **********************************************************/
/* @import "./css/buttons/buttons_on_menubar_toolbar_classic_appearance.css"; /**/

/* tabs toolbar - toolbar button appearance *****************************************************/
/* @import "./css/buttons/buttons_on_tabs_toolbar_classic_appearance.css"; /**/			/* <--- EXPERIMENTAL */

/* bookmarks menu button - 'button & popup' appearance ******************************************/
/*@import "./css/buttons/bookmarks_menu_button_localized_label_on_bookmarks_toolbar.css"; /**/
@import "./css/buttons/bookmarks_menu_button_popup_showall_top_hidden.css"; /**/
/* @import "./css/buttons/bookmarks_menu_button_popup_showall_bottom_hidden.css"; /**/
/* @import "./css/buttons/bookmarks_menu_button_popup_sidebar_item_hidden.css"; /**/
/* @import "./css/buttons/bookmarks_menu_button_popup_toolbar_item_hidden.css"; /**/
/* @import "./css/buttons/bookmarks_menu_button_popup_other_item_hidden.css"; /**/

/* other button settings ************************************************************************/
@import "./css/buttons/whatnew_button_always_hidden.css"; /**/
/* @import "./css/buttons/forward_button_hide_when_disabled.css"; /**/
/* @import "./css/buttons/back_and_forward_separated_history_popups.css"; /**/
/* @import "./css/buttons/back_and_forward_leftclick_history_popup_hidden.css"; /**/
/* @import "./css/buttons/zoom_buttons_hide_reset.css"; /**/
/* @import "./css/buttons/overflow_button_rotate_on_open.css"; /**/


/* CUSTOM BACK & FORWARD BUTTONS appearance - [only use one at a time] **************************/
/* @import "./css/buttons/custom_backforward_large_ff2.css"; /**/
/* @import "./css/buttons/custom_backforward_large_ff3.css"; /**/
/* @import "./css/buttons/custom_backforward_large_ff3_strata.css"; /**/
/* @import "./css/buttons/custom_backforward_large_ff3_strata_v2.css"; /**/
/* @import "./css/buttons/custom_backforward_large_ff3_strata_orange.css"; /**/
/* @import "./css/buttons/custom_backforward_large_ff3_strata_red.css"; /**/
/* @import "./css/buttons/custom_backforward_large_ie8.css"; /**/
/* @import "./css/buttons/custom_backforward_large_ie9.css"; /**/
/* @import "./css/buttons/custom_backforward_large_kempelton.css"; /**/
/* @import "./css/buttons/custom_backforward_small_ff3.css"; /**/
/* @import "./css/buttons/custom_backforward_small_ff3_strata.css"; /**/
/* @import "./css/buttons/custom_backforward_small_ff3_strata_orange.css"; /**/
/* @import "./css/buttons/custom_backforward_small_ff3_strata_red.css"; /**/
/* @import "./css/buttons/custom_backforward_small_ie8.css"; /**/
/* @import "./css/buttons/custom_backforward_small_ie9.css"; /**/
/* @import "./css/buttons/custom_backforward_small_kempelton.css"; /**/
/* @import "./css/buttons/custom_backforward_connected.css"; /**/ /* round */
/* @import "./css/buttons/custom_backforward_connected_to_location_bar.css"; /**/ /* round */
/* @import "./css/buttons/custom_backforward_connected_alt.css"; /**/ /* squared*/
/* @import "./css/buttons/custom_backforward_connected_to_location_bar_alt.css"; /**/ /* squared*/


/************************************************************************************************/
/* APPLICATION/HAMBURGER BUTTON *****************************************************************/
/************************************************************************************************/

/* application/hamburger button hidden - disable all other appbutton options when using this ****/
@import "./css/appbutton/appbutton_hidden.css"; /**/

/* application/hamburger button popup ***********************************************************/
@import "./css/appbutton/appbutton_popup_icons.css"; /**/
@import "./css/appbutton/appbutton_popup_icons_colorized.css"; /**/
/* @import "./css/appbutton/appbutton_popup_sync_hidden.css"; /**/
/* @import "./css/appbutton/appbutton_popup_logins_and_passwords_hidden.css"; /**/

/************************************************************************************************/
/* button on navigation toolbar *****************************************************************/
/************************************************************************************************/

/* @import "./css/appbutton/appbutton_on_navbar_start_position.css"; /**/

/* button color - [only use one at a time] ******************************************************/
/* @import "./css/appbutton/appbutton_on_navbar_color_autocolor.css"; /**/
/* @import "./css/appbutton/appbutton_on_navbar_color_autocolor57p.css"; /**/
/* @import "./css/appbutton/appbutton_on_navbar_color_orange.css"; /**/
/* @import "./css/appbutton/appbutton_on_navbar_color_aurora.css"; /**/
/* @import "./css/appbutton/appbutton_on_navbar_color_nightly.css"; /**/
/* @import "./css/appbutton/appbutton_on_navbar_color_deved57p.css"; /**/
/* @import "./css/appbutton/appbutton_on_navbar_color_nightly57p.css"; /**/
/* @import "./css/appbutton/appbutton_on_navbar_color_palemoon.css"; /**/

/* button icon - [only use one at a time] *******************************************************/
/* @import "./css/appbutton/appbutton_on_navbar_icon_white.css"; /**/
/* @import "./css/appbutton/appbutton_on_navbar_icon_dark.css"; /**/
/* @import "./css/appbutton/appbutton_on_navbar_icon_grey.css"; /**/
/* @import "./css/appbutton/appbutton_on_navbar_icon_browser_logo.css"; /**/

/* button label (show label besides icon) *******************************************************/
/* @import "./css/appbutton/appbutton_on_navbar_icon_and_label.css"; /**/


/************************************************************************************************/
/* button in Firefox titlebar *******************************************************************/
/************************************************************************************************/

/* button in titlebar - [only use one at a time] ************************************************/
@import "./css/appbutton/appbutton_in_titlebar.css"; /**/ /* <-- label only */
/* @import "./css/appbutton/appbutton_in_titlebar_icon_only.css"; /**/

/* for 'appbutton in titlebar icon only' - [only use one at a time] *****************************/
/* @import "./css/appbutton/appbutton_in_titlebar_icon_only_dark.css"; /**/
/* @import "./css/appbutton/appbutton_in_titlebar_icon_only_grey.css"; /**/
/* @import "./css/appbutton/appbutton_in_titlebar_icon_only_browser_logo.css"; /**/

/* for 'appbutton in titlebar icon only' ********************************************************/
/* @import "./css/appbutton/appbutton_in_titlebar_label_and_icon.css"; /**/

/* macOS fix - appbutton in titlebar gets moved to the right ************************************/
/* @import "./css/appbutton/appbutton_in_titlebar_macOS_fix.css"; /**/

/* button color - [only use one at a time] ******************************************************/
@import "./css/appbutton/appbutton_in_titlebar_autocolor.css"; /**/
/* @import "./css/appbutton/appbutton_in_titlebar_autocolor57p.css"; /**/
/* @import "./css/appbutton/appbutton_in_titlebar_transparent.css"; /**/
/* @import "./css/appbutton/appbutton_in_titlebar_semi_transparent.css"; /**/
/* @import "./css/appbutton/appbutton_in_titlebar_aurora.css"; /**/
/* @import "./css/appbutton/appbutton_in_titlebar_nightly.css"; /**/
/* @import "./css/appbutton/appbutton_in_titlebar_deved57p.css"; /**/
/* @import "./css/appbutton/appbutton_in_titlebar_nightly57p.css"; /**/
/* @import "./css/appbutton/appbutton_in_titlebar_palemoon.css"; /**/


/************************************************************************************************/
/* TABS - appearance and position ***************************************************************/
/************************************************************************************************/

/* custom tab appearance - [only use one at a time] *********************************************/
@import "./css/tabs/classic_squared_tabs.css"; /**/
/* @import "./css/tabs/classic_squared_tabs_australized.css"; /**/
/* @import "./css/tabs/default_tabs_enhanced.css"; /**/

/* custom tab colors are set inside color_variables***.css file(s) ******************************/

/* remove top corner roundness ******************************************************************/
/* @import "./css/tabs/classic_squared_tabs_fully_squared.css"; /**/


/************************************************************************************************/
/* TABS TOOLBAR POSITION (below titlebar / below navigation toolbar / below main content) *******/
/************************************************************************************************/

/* [only use one at a time] - BELOW TITLEBAR or BELOW NAVIGATION BAR or BELOW MAIN CONTENT ******/

/* - TABS BELOW TITLEBAR (Fx56-like) ************************************************************/
/* @import "./css/tabs/tabs_below_titlebar_above_navigation_toolbar.css"; /**/

/* - TABS BELOW NAVIGATION AND BOOKMARKS TOOLBARS / TABS NOT ON TOP *****************************/
/* [!] Note: do not use OS titlebar with 'tabs not on top' code on macOS ************************/
/* [!] Note: only 'alt' works with multi-tab lines option. **************************************/
/* - Windows/Linux ******************************************************************************/
/* [!] might require overriding url bars 'selection color' --> see corresponding area ***********/ 
@import "./css/tabs/tabs_below_navigation_toolbar.css"; /**/
/* @import "./css/tabs/tabs_below_navigation_toolbar_default_tabs.css"; /**/
/* - macOS **************************************************************************************/
/* @import "./css/tabs/tabs_below_navigation_toolbar_macOS.css"; /**/
/* @import "./css/tabs/tabs_below_navigation_toolbar_macOS_default_tabs.css"; /**/

/* - Alternative for multi-lined tabs (Glitches with inactive menubar!) ******************/  /* <- use this for multiple tab lines support */
/* @import "./css/tabs/tabs_below_navigation_toolbar_alt.css"; /**/
/* @import "./css/tabs/tabs_below_navigation_toolbar_alt_force_hidden_menubar.css"; /**/ /* no menubar when OS titlebar is active */
/* @import "./css/tabs/tabs_below_navigation_toolbar_alt_macOS.css"; /**/

/* - TABS BELOW MAIN CONTENT (tabs on bottom) - EXPERIMENTAL ************************************/
/* [!] SUPPORT THREAD: https://github.com/aris-t2/customcssforfx/issues/33 **********************/
/* [!] not compatible to 'tabs toolbar - multiple tab lines' option *****************************/
/* - Windows/Linux ***********************************************************************/
/* @import "./css/tabs/tabs_below_main_content.css"; /**/

/* - MOVE NAVIGATION TOOLBAR TO HIGHER POSITON (for tabs not on top) - [only use one at a time] */
/* @import "./css/tabs/tabs_below_navigation_toolbar_higher_navbar_positon.css"; /**/			/* <--- EXPERIMENTAL */
/* @import "./css/tabs/tabs_below_navigation_toolbar_higher_navbar_positon_with_appbutton.css"; /**/  /* <--- EXPERIMENTAL */
/* @import "./css/tabs/tabs_below_navigation_toolbar_higher_navbar_positon_with_appbutton_icon_only.css"; /**/  /* <--- EXPERIMENTAL */


/* TAB BACKGROUND COLORS for default/active/hovered/unloaded tabs and 'new tab' tab *************/
/* edit target file to set own custom colors ****************************************************/
/* @import "./config/custom_tab_color_settings.css"; /**/
/* TAB TEXT colors/shadow/weight/style for default/active/hovered/unloaded tabs *****************/
/* edit target file to set own custom colors ****************************************************/
/* @import "./config/custom_tab_text_settings.css"; /**/

/* MULTIROW / multi lined tabs - [only use one at a time] ***************************************/
/* [!] EXPERIMENTAL (any Fx update might break this highly experimental feature) ****************/
/* [!] SUPPORT THREAD: https://github.com/aris-t2/customcssforfx/issues/39 **********************/
/* [!] BUG: dragging tabs does not work with multi lined tabs ***********************************/
/* [!] Original authors: --> https://00.bulog.jp/archives/1476 **********************************/
/* [!] --> https://www.reddit.com/r/FirefoxCSS/comments/7dclp7/multirow_tabs_in_ff57/ ***********/
/* [!] not compatible with 'tabs toolbar - below main content' option ***************************/
/* [!] only compatible with 'tabs below navigation toolbar alt version' *************************/
/* @import "./css/tabs/tabs_multiple_lines.css"; /**/
/* @import "./css/tabs/tabs_multiple_lines_force_newtab_button_visibility.css"; /**/


/* restore empty/missing tab favicon - [only use one at a time] *********************************/
@import "./css/tabs/missing_tab_favicon_restored_default.css"; /**/
/* @import "./css/tabs/missing_tab_favicon_restored_globe_v2.css"; /**/
/* @import "./css/tabs/missing_tab_favicon_restored_sheet.css"; /**/
/* @import "./css/tabs/missing_tab_favicon_restored_dotted.css"; /**/
/* @import "./css/tabs/missing_tab_favicon_restored_dotted_white.css"; /**/
/* @import "./css/tabs/missing_tab_favicon_restored_brand_logo.css"; /**/

/* custom tab loading animation - [only use one at a time] **************************************/
/* @import "./css/tabs/tab_throbber_blue_fx56.css"; /**/ /* known from Fx 56 */
/* @import "./css/tabs/tab_throbber_blue.css"; /**/
/* @import "./css/tabs/tab_throbber_grey_classic.css"; /**/
/* @import "./css/tabs/tab_throbber_green.css"; /**/
/* @import "./css/tabs/tab_throbber_orange_ubuntu.css"; /**/

/* tab close icon settings - [only use one at a time] *******************************************/
@import "./css/tabs/tab_close_always_visible.css"; /**/
/* @import "./css/tabs/tab_close_on_active_tab_only.css"; /**/
/* @import "./css/tabs/tab_close_show_on_hover_only.css"; /**/
/* @import "./css/tabs/tab_close_hidden.css"; /**/
/* @import "./css/tabs/tab_close_hidden_for_only_one_visible_tab.css"; /**/
/* @import "./css/tabs/tab_close_at_tabs_start.css"; /**/
/* @import "./css/tabs/tab_close_icon_size.css"; /**/

/* tab title - [only use one at a time] *********************************************************/
/* @import "./css/tabs/tab_title_left.css"; /**/
/* @import "./css/tabs/tab_title_centered.css"; /**/
/* @import "./css/tabs/tab_title_right.css"; /**/

/* DEFAULT TABS - use only, if 'classic squared tabs' are disabled ******************************/
/* tab line settings - [only use one at a time] *************************************************/
/* @import "./css/tabs/default_tabs_no_tab_line.css"; /**/
/* @import "./css/tabs/default_tabs_tab_line_red_for_unloaded_tabs.css"; /**/
/* @import "./css/tabs/default_tabs_tab_line_purple_in_private_mode.css"; /**/

/* other tab settings ***************************************************************************/
@import "./css/tabs/tab_icon_colors.css"; /**/
/* @import "./css/tabs/tab_audio_icon.css"; /**/
/* @import "./css/tabs/newtab_tab_size_equals_tab_size.css"; /**/
/* @import "./css/tabs/newtab_button_always_visible.css"; /**/
/* @import "./css/tabs/tab_icon_inactive_tabs_lower_opacity.css"; /**/
/* @import "./css/tabs/tab_icon_unloaded_tabs_lower_opacity.css"; /**/
/* @import "./css/tabs/tab_maxwidth.css"; /**/
/* @import "./css/tabs/tab_titles_remove_blur.css"; /**/
/* @import "./css/tabs/alltabs_button_always_visible.css"; /**/  /* <--- hidden, if multiple tab rows are used */
/* @import "./css/tabs/pinnedtab_empty_favicon_hidden.css"; /**/
/* [!] edit target file to select which items to hide *******************************************/
/* @import "./css/tabs/tab_context_menuitems_visibility.css"; /**/


/************************************************************************************************/
/* GENERAL UI ***********************************************************************************/
/************************************************************************************************/

/* context menus / menupopups / panels **********************************************************/
@import "./css/generalui/popup_compact_menus.css"; /**/
/* @import "./css/generalui/popup_compact_menus_squared.css"; /**/
/* @import "./css/generalui/popup_animation_fade_time_reduced.css"; /**/
/* @import "./css/generalui/popup_items_hover_appearance_aero.css"; /**/
/* @import "./css/generalui/popup_menupopup_with_scrollbars.css"; /**/  /* <- this removes tab scroll buttons, no CSS fix possible atm */

@import "./css/generalui/private_mode_indicator_hidden.css"; /**/
@import "./css/generalui/bookmark_icons_colorized.css"; /**/
/* @import "./css/generalui/bookmarks_smaller_more_bookmarks_icon.css"; /**/
/* @import "./css/generalui/send_to_device_menuitems_hidden.css"; /**/
/* @import "./css/generalui/set_as_desktop_background_menuitems_hidden.css"; /**/
/* @import "./css/generalui/increase_ui_font_size.css"; /**/
/* @import "./css/generalui/flex_space_on_navbar_replace_with_separator.css"; /**/
/* @import "./css/generalui/statusbar_color.css"; /**/
/* @import "./css/generalui/classic_drop_indicator.css"; /**/
/* @import "./css/generalui/notification_old_size.css"; /**/

/* overflow menu - [only use one at a time] *****************************************************/
/* @import "./css/generalui/overflow_menu_remove_text.css"; /**/
/* @import "./css/generalui/overflow_menu_horizontal_remove_text.css"; /**/

/* sidebar **************************************************************************************/
/* @import "./css/generalui/sidebar_items_compact.css"; /**/
/* @import "./css/generalui/sidebar_header_icons_colorized.css"; /**/
/* @import "./css/generalui/sidebar_header_lwtheme.css"; /**/
/* sidebar dimensions - [only use one at a time] ************************************************/
/* @import "./css/generalui/sidebar_show_on_hover.css"; /**/
/* @import "./css/generalui/sidebar_width_unrestricted.css"; /**/
/* sidebar appearance - [only use one at a time] ************************************************/
/* @import "./css/generalui/sidebar_appearance_grey.css"; /**/
/* @import "./css/generalui/sidebar_appearance_grey_v2.css"; /**/
/* @import "./css/generalui/sidebar_appearance_dark.css"; /**/
/* @import "./css/generalui/sidebar_appearance_dark_v2.css"; /**/
/* @import "./css/generalui/sidebar_appearance_lwtheme_bright.css"; /**/
/* @import "./css/generalui/sidebar_appearance_lwtheme_dark.css"; /**/


/* FINDBAR **************************************************************************************/
/* @import "./css/generalui/findbar_on_top.css"; /**/
/* @import "./css/generalui/findbar_on_top_close_at_findbars_start.css"; /**/
/* @import "./css/generalui/findbar_compact.css"; /**/


/* page context menu items: 'back', 'forward', 'reload', 'stop', 'bookmarks' ********************/
/* @import "./css/generalui/context_bfrsb_icons_colorized.css"; /**/
/* menuitem labels - [only use one at a time] ***************************************************/
@import "./css/generalui/context_bfrsb_labels_without_icons.css"; /**/
/* @import "./css/generalui/context_bfrsb_labels_with_icons.css"; /**/

/* close icons for general ui and tabs - [only use one at a time] *******************************/
/* @import "./css/generalui/close_icon_windows7.css"; /**/
/* @import "./css/generalui/close_icon_windows7inverted.css"; /**/
/* @import "./css/generalui/close_icon_windows7v2.css"; /**/
/* @import "./css/generalui/close_icon_gchrome.css"; /**/
/* @import "./css/generalui/close_icon_red.css"; /**/
/* @import "./css/generalui/close_icon_windows10.css"; /**/
/* @import "./css/generalui/close_icon_windows10inverted.css"; /**/
/* @import "./css/generalui/close_icon_windows10red.css"; /**/
/* @import "./css/generalui/close_icon_windows10redv2.css"; /**/
/* @import "./css/generalui/close_icon_firefox3.css"; /**/

/* SEARCHBAR ************************************************************************************/
@import "./css/generalui/searchbar_glassplus_indicator_hidden.css"; /**/
/* @import "./css/generalui/searchbar_go_button_hidden.css"; /**/

/* searchbar popup ******************************************************************************/
/* @import "./css/generalui/searchbar_popup_current_engine_hidden.css"; /**/
/* searchbar popup - search engine settings - [only use one at a time] **************************/
/* @import "./css/generalui/searchbar_popup_engines_hidden.css"; /**/
/* @import "./css/generalui/searchbar_popup_engines_show_labels.css"; /**/
/* @import "./css/generalui/searchbar_popup_engines_show_labels_scrollbars.css"; /**/

/* MENUBARS bookmarks popup (not compatible to macOS/Linux) *************************************/
/* @import "./css/generalui/menubar_bookmarks_popup_bookmark_page_item_hidden.css"; /**/
/* @import "./css/generalui/menubar_bookmarks_popup_subscribe_item_hidden.css"; /**/
/* @import "./css/generalui/menubar_bookmarks_popup_toolbar_item_hidden.css"; /**/
/* @import "./css/generalui/menubar_bookmarks_popup_other_item_hidden.css"; /**/


/************************************************************************************************/
/* TOOLBARS *************************************************************************************/
/************************************************************************************************/

/* ADDON BAR - simulate add-on bar by moving bookmarks toolbar to the bottom ********************/
/* [!] move 'Bookmarks Toolbar Items' to navigation bar to get a top toolbar with bookmarks *****/
/* [!] not compatible to 'bookmarks toolbar - multiple lines' option ****************************/
/* [!] not compatible to 'bookmarks toolbar autohide' option ************************************/
/* [!] SUPPORT THREAD: https://github.com/aris-t2/customcssforfx/issues/73 **********************/
/* @import "./css/toolbars/addonbar_move_bookmarks_toolbar_to_bottom.css"; /**/  /* <--- EXPERIMENTAL */
/* @import "./css/toolbars/addonbar_move_bookmarks_toolbar_to_bottom_tabs_on_bottom_compatibility.css"; /**/  /* <--- EXPERIMENTAL */
/* @import "./css/toolbars/addonbar_content_on_the_right.css"; /**/  /* <--- EXPERIMENTAL */
/* @import "./css/toolbars/addonbar_status_in_addonbar.css"; /**/  /* <--- EXPERIMENTAL */
/* @import "./css/toolbars/addonbar_fullscreen_autohide.css"; /**/  /* <--- EXPERIMENTAL */
/* [!] create additional toolbar for 'bookmarks toolbar items' on navigation toolbar ************/
/* @import "./css/toolbars/addonbar_extra_bookmarks_toolbar_below_navbar.css"; /**/  /* <--- EXPERIMENTAL */
 
/* GENERAL TOOLBAR SETTINGS *********************************************************************/
/* @import "./css/toolbars/top_toolbar_OS_accent_colors.css"; /**/ /* restore window accent color managed by the OS */
/* @import "./css/toolbars/top_toolbar_colors.css"; /**/ /* override tabs toolbar / titlebar colors forced by Proton UI */
@import "./css/toolbars/toolbars_old_padding.css"; /**/
@import "./css/toolbars/tabs_toolbar_adjustments.css"; /**/
/* @import "./css/toolbars/tabs_toolbar_adjustments_macOS_fix.css"; /**/					/*  <-- macOS fix */

/* edit target file to select which items to hide ***********************************************/
/* @import "./css/toolbars/toolbar_context_menuitems_visibility.css"; /**/

/* MENUBAR **************************************************************************************/
/* @import "./css/toolbars/menubar_fog_hidden.css"; /**/
/* @import "./css/toolbars/menubar_alternative_menu_hover_color.css"; /**/
/* @import "./css/toolbars/menubar_in_fullscreen_mode.css"; /**/
/* @import "./css/toolbars/menubar_in_fullscreen_mode_alt.css"; /**/ /*'tabs not on top alt' */
/* menubar color - ******************************************************************************/
/* @import "./css/toolbars/menubar_color.css"; /**/

/* BOOKMARKS TOOLBAR ****************************************************************************/
@import "./css/toolbars/bookmarks_toolbar_old_height.css"; /**/
/* @import "./css/toolbars/bookmarks_toolbar_fixed_width.css"; /**/
/* @import "./css/toolbars/bookmarks_toolbar_autohide.css"; /**/
/* @import "./css/toolbars/bookmarks_toolbar_bookmark_labels_hidden.css"; /**/
/* @import "./css/toolbars/bookmarks_toolbar_in_fullscreen_mode.css"; /**/
/* [!] simulate second bookmarks toolbar while "Bookmarks Toolbar Items" element is on nav-bar **/
/* @import "./css/toolbars/bookmarks_toolbar_simulate_second_bm_toolbar.css"; /**/

/* BOOKMARKS TOOLBAR above navigation toolbar - [only use one at a time] ************************/
/* @import "./css/toolbars/bookmarks_toolbar_above_navigation_toolbar.css"; /**/
/* @import "./css/toolbars/bookmarks_toolbar_above_navigation_toolbar_when_tab_not_top.css"; /**/

/* BOOKMARKS TOOLBAR - MULTIPLE LINES - [only use one at a time] ********************************/
/* [!] the amount of visible bookmark items is limited internally to ~90-110 bookmarks **********/
/* [!] not compatible to 'bookmarks toolbar autohide' option ************************************/
/* [!] not compatible to 'simulated second bookmarks toolbar' option ****************************/
/* [!] not compatible to 'simulated addon-bar' option *******************************************/
/* [!] SUPPORT THREAD: https://github.com/aris-t2/customcssforfx/issues/99 **********************/
/* @import "./css/toolbars/bookmarks_toolbar_multiple_lines.css"; /**/ /* <--- EXPERIMENTAL */

/* TOOLBAR COLORS *******************************************************************************/
@import "./css/toolbars/general_toolbar_colors.css"; /**/
/* @import "./css/toolbars/tab_toolbar_colors_force_menubar_color.css"; /**/

/* AeroGlass TOOLBARS - separated - set per toolbar / WIN10 fix for GLASS8 **********************/
/* @import "./css/toolbars/general_toolbar_colors_navigation_toolbar_aeroglass.css"; /**/
/* @import "./css/toolbars/general_toolbar_colors_bookmarks_toolbar_aeroglass.css"; /**/
/* @import "./css/toolbars/general_toolbar_colors_tabs_toolbar_aeroglass.css"; /**/
/* Windows 10 fix for Glass8 - Glass8 required for 'Windows 7'-like window transparency */
/* @import "./css/toolbars/general_toolbar_colors_aeroglass_windows10_glass8.css"; /**/  /* <--- EXPERIMENTAL */

/* TOOLBAR TEXT MODES - [only use one at a time] ************************************************/
/* @import "./css/toolbars/toolbar_mode_icons_and_text.css"; /**/
/* @import "./css/toolbars/toolbar_mode_icons_and_text_macOS.css"; /**/ /* -> also offers alternative appearance on Linux */
/* @import "./css/toolbars/toolbar_mode_text.css"; /**/
/* @import "./css/toolbars/toolbar_mode_text_macOS.css"; /**/ /* -> also offers alternative appearance on Linux */


/************************************************************************************************/
/* LOCATION BAR / MEGABAR - Settings for both 'about:config > browser.urlbar.update1' cases *****/
/************************************************************************************************/

/* remove color formatting of the url: about:config > browser.urlbar.formatting.enabled > false */

/* @import "./css/locationbar/compact_mode_reduce_fontsize.css"; /**/

/* identity box / page identity button **********************************************************/
@import "./css/locationbar/identitybox_colors.css"; /**/
/* @import "./css/locationbar/identitybox_labels_hidden.css"; /**/

/* padlock icons in identity box / page identity button - [only use one at a time] **************/
/* @import "./css/locationbar/identitybox_padlock_icon_classic.css"; /**/
/* @import "./css/locationbar/identitybox_padlock_icon_classic2.css"; /**/
/* @import "./css/locationbar/identitybox_padlock_icon_modern.css"; /**/
/* @import "./css/locationbar/identitybox_padlock_icon_modern2.css"; /**/
/* @import "./css/locationbar/identitybox_padlock_icon_hidden.css"; /**/

/* additional icons/buttons and tweaks for third party page action buttons **********************/
/* @import "./css/locationbar/reader_alternative_icon.css"; /**/
/* @import "./css/locationbar/popup_blocked_button_hidden.css"; /**/
/* @import "./css/locationbar/zoom_button_hidden.css"; /**/
/* @import "./css/locationbar/go_button_in_location_bar_hidden.css"; /**/

/* star button / bookmarks star *****************************************************************/
@import "./css/locationbar/starbutton_popup_preview_image_hidden.css"; /**/
/* alternative yellow star icon - [only use one at a time] **************************************/
/* @import "./css/locationbar/starbutton_alternative_icon.css"; /**/
/* @import "./css/locationbar/starbutton_alternative_icon_v2.css"; /**/

/* general popup/results settings ***************************************************************/
/* @import "./css/locationbar/ac_popup_result_font_size.css"; /**/
/* @import "./css/locationbar/ac_popup_firefox_background_logo.css"; /**/

/* selection color / force selection color on themes without predefined selection color *********/
/* @import "./css/locationbar/selection_color_for_dark_bg.css"; /**/
/* @import "./css/locationbar/selection_color_for_bright_bg.css"; /**/

 
/************************************************************************************************/
/* MEGABAR - settings for 'megabar' & 'megabar popup' *******************************************/
/************************************************************************************************/

@import "./css/locationbar/megabar_expanding_breakout_disabled.css"; /**/
/* @import "./css/locationbar/megabar_disable_openviewonfocus.css"; /**/
/* @import "./css/locationbar/megabar_border_roundness.css"; /**/
/* @import "./css/locationbar/megabar_background_color_dark.css"; /**/
/* @import "./css/locationbar/urlbar_background_color.css"; /**/ /* Fx89+ */

/* popup content order/appearance - [only use one at a time] ************************************/
@import "./css/locationbar/ac_popup_megabar_title_and_url_50percent_width.css"; /**/
/* @import "./css/locationbar/ac_popup_megabar_url_and_title_50percent_width.css"; /**/
/* @import "./css/locationbar/ac_popup_megabar_title_and_url_two_lines.css"; /**/
/* @import "./css/locationbar/ac_popup_megabar_url_only.css"; /**/ 

/* result menuitem settings/appearance **********************************************************/
@import "./css/locationbar/ac_popup_megabar_compact_results.css"; /**/
/* @import "./css/locationbar/ac_popup_megabar_searchwith_and_visit_items_hidden.css"; /**/
/* @import "./css/locationbar/ac_popup_megabar_search_engines_hidden.css"; /**/
/* @import "./css/locationbar/ac_popup_megabar_result_highlighting_aero.css"; /**/
/* @import "./css/locationbar/ac_popup_megabar_result_separator.css"; /**/


/************************************************************************************************/
/************************************************************************************************/
/* Create a new file "my_userChrome.css" and add own/custom code to it. *************************/
@import "./my_userChrome.css"; /**/
/************************************************************************************************/
/************************************************************************************************/
/************************************************************************************************/

In the code tags...it's fairly small, but if I had to edit this post...I would have to scroll through the whole thing, every time.

Firefox 91.0.1 is out, no adjustment to tweaks are necessary...yet.

Latest Firefox released for Windows [2]