Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

yes, the issue presists.

Maybe your graphics drivers need to be updated, see :

https://support.mozilla.org/en-US/kb/upgrade-graphics-drivers-use-hardware-acceleration

If that doesn't solve the problem, would you try this please :

3-bar menu (or 'Tools') => Options => Advanced => General tab : under 'Browsing' : uncheck 'Use hardware acceleration when available'

It is possible that Firefox has a problem with the font that is used.

You can right-click and select "Inspect Element" to open the builtin Inspector with this element selected. You can check the font used for selected text in the Font tab in the right pane of the Inspector.

• https://developer.mozilla.org/en/Tools/Page_Inspector
• https://developer.mozilla.org/en/Tools/Page_Inspector/How_to/View_fonts

Happy112 said

Maybe your graphics drivers need to be updated, see : https://support.mozilla.org/en-US/kb/upgrade-graphics-drivers-use-hardware-acceleration If that doesn't solve the problem, would you try this please : 3-bar menu (or 'Tools') => Options => Advanced => General tab : under 'Browsing' : uncheck 'Use hardware acceleration when available'

nope, didn't helped. my gpu driver was updated after that and not in the same day and the issue still persists.

that option is not available, probably disabled in the code by the maintainers of the distro.

cor-el said

It is possible that Firefox has a problem with the font that is used. You can right-click and select "Inspect Element" to open the builtin Inspector with this element selected. You can check the font used for selected text in the Font tab in the right pane of the Inspector.

• https://developer.mozilla.org/en/Tools/Page_Inspector
• https://developer.mozilla.org/en/Tools/Page_Inspector/How_to/View_fonts

but my issue is in the menu entries too (as can be seen in the screenshot above.) regardless, I've tried to change the fonts and it didn't solved the issue on hand.

Suggestion; install Firefox v54 until you can Update Firefox to the latest version 55.0.3

https://support.mozilla.org/en-US/kb/install-older-version-of-firefox?cache=no Be sure to read everything here.

If you still want to downgrade, look under; I still want to downgrade. Click the Directory of other versions and languages link. Look for the directory of the version that you want. But, remember that old versions may have security issues.

You should also check out Firefox; Extended Support Release {web link} ESR Notes System Requirements

ok, found the issue, there is an optimization named pgo. I've disabled it and rebuilt the firefox.

all works ok now. will report this to the distro maintainers.

thankd for the help.

Glad to help. Safe Surfing.