@burnout426 Check. I tried Hardware acceleration turned off but to no avail.

@lowlife9: The lack of color in high contrast theme mode is more apparent in "Windows 10" than "Windows 8.1"
I've got to say this sort of thing does not happen in FireFox in either windows???

Opera Chrome and Edge all the same in a triumvirate of anti-contrast.
I can not use Stylus any more, what has happened?
All my speed dials have black bands for writing and pictures gone in "High Contrast"
I do not want to use stupid windows theme.
I need syntax highlight.
With windows I have to go high contrast.
Firefox only browser useable unless change windows theme.
Is this "The End"

75.3939 works now Thanx a lot!

Yes having delved deep into the mysterious crash reports. Dark.UI is repeated.
Reset ui in 74 then back to 75.
Swapping between Light to Dark in 75 makes a crash!?
I shall try to find reason why. I do not want to reset everything.

~ "Dark mode ui with odd color and size adjustments strike again" ~

75 still works but........ DEBUG.LOG says
crashpad_client_win.cc(522)] CreateProcess:
registration_protocol_win.cc(103) CreateFile:
-> The system cannot find the file specified.
............could that be cos i deleted them?

Possible culprits.
.\installer.exe
.\installer_helper_64.exe
.\installer_helper_lib.dll
.\launcher.exe
.\notification_helper.exe
.\opera_autoupdate.exe
.\opera_crashreporter.exe
A motley crew!

The epilog:
I have no use for these persistently annoying files except for launcher and that famous egyptian or is it chinese song and dance "SANDBOX" in linux.

74.0.3904.0 | 14-Dec-2020 14:46

At this point upgrade to 75 results in a "non-starter".

75.0.3925.0 | 04-Jan-2021 12:08
75.0.3932.0 | 11-Jan-2021 12:37

I have installed separate version 75 and all fine.
Can only think settings of some sort are now out of sync for upgrade route?

@lowlife9 Interesting fact.
You cannot copy paste a standard table from any browser to WordPad except good ole "Internet Explorer"

@gmiazga I think you may have nailed the point into the beast.
I will await with baited breath as to the illustrious findings from "The High Contrast Theme" team
cos yr right na funny menus wen i'm in placid blindin white and pastel shades of pastoral magnolia.
Windows Default Theme.

@leocg I thought this was a singular topic of individuality.

@burnout426 Check. I tried Hardware acceleration turned off but to no avail.

@burnout426
Here is yet another unusual one