Taskbar right-click menu and system tray icons delay

Hello,

recently my system has developed a weird issue. Right-clicking on the taskbar on any open applications that I have stops working quite often (the black task menu to minimize/close etc doesn't appear), meaning: after logging in it's all good, then after a while it won't appear, or if it does, it's with enormous lag. So basically it goes back and forth, having periods when all is at it should, but then not working when I want it to, there's no consistency. Right-clicking anywhere else: on desktop, unused area of the taskbar is without delay. I've tried sfc /scannow which found some errors to repair, then I used DISM /Online /Cleanup-Image commands (3 different to check, scan and repair). Went through all of that, it finished, then tried sfc /scannow again, it finished its repairs, but the issue prevails.

The same lag/delay applies when I try to left-click on system tray icons that I have: power, connections and volume. They either appear with very long delay or don't work at all, then if they work, they do so for a short while and then stop functioning again.

What can I do to solve these?
Win 10 Pro x64 version 1703 OS build 15063.540

Thanks,
zil

You should be able to fix this issue by changing the settings for the power plan. a. Click on start button, type power option and press enter.b. Select High performance power plan. (If you don't see High performance option then, search for it underHide additional plans.)c. Now check for the issue.

I always have high performance mode on.

Okay, it seems I've found something, finally. I bumped into it quite randomly after seeing a recent Windows Update package KB4034674 in the Programs and Features uninstall list. I looked into it on Google with the package nr and "right click" as keywords and found this solution:

Windows 10 Taskbar Icon Right-Click broken after Windows Update KB4034674 - Super User

Basically, you just have to go and uninstall KB4034674 package, nothing else. After doing that, the problem seems to have disappeared. On the downside, though, the lock screen, which I had previously disabled, is back. I would like to get rid of it, as it was before, but that is a different topic.