Here is one post I saw.
Windows 10 1809 - Missing Display Options
They said they did clean and got same results.
More
https://answers.microsoft.com/en-us/windows/forum/windows_10-update/windows-brightness-issue-after-the-1809-update/2a1689ae-5625-4679-9ab7-3f754cb8111b?page=4
and pretty sure I saw comments about Adaptive Brightness in that very long 1809 thread.
Is this what you meant Do tell?
The problem that you are having is related to Windows 10 upgrade to build 1809 on HP computers.
You can rollback to 1803 within 10 days:
Go Back to the Previous Version of Windows in Windows 10 | Windows 10 Tutorials
Gonna fresh install 1803. This was a fresh install, but I got ISO from a Russian website via Facebook?
Gort
See this link (also on some Dell computers)
Brightness at 50% every reboot after October 2018 Update - Windows 10 Forums
Oh, why? Do you trust the Russians?
Windows 10 Recovery Tools - Bootable Rescue Disk - Windows 10 Forums
- see iso tool post #3
Back on 1803. Now I find I cannot set firefox as default pdf reader. The fun never ends What next, I reboot and land on Mars.
Gort
Are the display settings back to norm?
For PDF reading I've used Adobe and have not troubleshooted failure to use Firefox.
This link may be useful:
View PDF files in Firefox | Firefox Help
Yes they are back to normal. Usually to set Firefox as default, I have to first use open with on a pdf file. Then I can go to settings, apps, default by file type and set it. Now when I do it MS Edge refuses to yield. Not really into Adobe Reader, but I might try again.
Gort
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