[tor-bugs] #26247 [Applications/Tor Browser]: On some chrome pages (about:addons) are tooltips just a black bar on Linux

[Tor Bug Tracker & Wiki]

#26247: On some chrome pages (about:addons) are tooltips just a black bar on Linux
--------------------------------------+--------------------------
 Reporter:  gk                        |          Owner:  tbb-team
     Type:  defect                    |         Status:  new
 Priority:  Medium                    |      Milestone:
Component:  Applications/Tor Browser  |        Version:
 Severity:  Normal                    |     Resolution:
 Keywords:  ff60-esr                  |  Actual Points:
Parent ID:                            |         Points:
 Reviewer:                            |        Sponsor:
--------------------------------------+--------------------------

Comment (by joebt):

 Absolutely, GK!  I've tried off & on ever since TBB started using Firefox
 Quantum.  Sadly, I can't make it my full time job.
 I have found a few things that may help others find a solution.  Maybe a
 bug needs filing w/ Mozilla.

 I used a custom GTK full theme (Cinnamon DE in Mint 18.1).  It worked fine
 for Fx & TBB until TBB used the 1st Fx quantum version.  Still works for
 Fx - now 63.x (not ESR).  I'm not sure if the ESR version is the problem,
 or some mods that have to be done for TBB.

 I can switch to most themes included w/ the Mint distro, and instantly the
 dark on dark tooltip issue is solved.  Except the Adwaita theme - still
 has the dark tooltips, but it's written differently than the other Mint-X
 & Mint-Y themes.  The Mint-x lighter or dark themes work for the tooltips,
 so it's not *just* a matter of theme color.

 I also found that if I copy a theme that doesn't have tooltip issues from
 /usr/share/themes, to ~/.themes and the only change is renaming it like
 "Mint-X-Aqua-1", or else the copied version still with the same name won't
 show in the theme selection UI.  That should have nothing to do with how
 TBB handles tooltips.  But it does.  Once copied to home dir, where copies
 of all the gtk2 theming engines also are, for some reason the dark on dark
 tooltips start immediately.  Yes, I verified that the directories of
 original theme in /usr were identical to ones I copied to ~/home.

 No amount of changes to the theme code for tooltips stops the issue, but
 those changes do affect regular Fx 57 - 63 as expected. Buried somewhere
 in TBB is something blocking the theme code, once copied to my home dir,
 but the theme copies in /home don't bother regular Fx Quantum.

 I went into the themes in TBB's omni.ja to see if I could stumble onto
 anything odd.  Nothing yet.
 I haven't had success w/ code in userChrome.css to try & force TBB to use
 that - adding -moz-appearance: none !important;, and putting "!important"
 after all colors - but no luck.

 Someone said there was a post on Ubuntu forums that using an Agent Sheet
 might work & they listed a slew of tooltip identifiers.
 Haven't tried it, but if it works that doesn't tell what the problem is,
 just puts a band-aide on it.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/26247#comment:1>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online