Same issue with the message tray. The "Clear all" button at the bottom is totally illegible (the very same shade of light grey it seems). It's barely legible when the mouse hover the button (white on light grey). 

Gnome classic, fresh install.

Created attachment 1301171 [details]
Screenshot of the message tray

In the mean time, is there a workaround? Can we set the color of notification somehow?

(In reply to Jerome Marchand from comment #3)
> In the mean time, is there a workaround? Can we set the color of
> notification somehow?

This is is really annoying, so I dug a bit. I came to to following file:
/usr/share/gnome-shell/theme/gnome-classic.css

It contains a section for the notification banner:

.notification-banner {
  font-size: 11pt;
  width: 34em;
  margin: 5px;
  border-radius: 6px;
  color: #eeeeec;
  background-color: #2e3436;
  border: 1px solid #a1a1a1; }
  .notification-banner:hover {
    background-color: #2e3436; }
  .notification-banner:focus {
    background-color: #2e3436; }

See the dark background colors above. I don't know what determines the color of the text itself (currently black), so I made a custom theme that only redefines  the background with a lighter color and it seems to work.

Hi, this seems to be still issue. Any progress here?

I am also experiencing this annoying bug, Gnome 3.24 on Fedora 26.

And also with gnome-shell-3.26.2-1.fc27 on Fedora 27.

Upstream issue:
https://bugzilla.gnome.org/show_bug.cgi?id=783826

Jerome Marchand, thank you for locating the CSS property. I'll modify it manually as the users I support are complaining.

It seems fairly absurd that this is still a problem in RHEL 7.  I'll submit a customer support request to see if they plan on fixing such an ugly UI problem on their flagship product.

Created 02038090 to try to get someone to field the issue.

Guys, I had the same problem with Fedora 27.
Here is my patch that makes it readable:

*** gnome-classic.css	2018-04-20 14:58:12.105081356 +0200
--- gnome-classic.css_dist	2018-03-19 14:40:49.072505704 +0100
***************
*** 901,910 ****
    width: 31.5em; }
  
  .message-list-clear-button.button {
!   background-color: #b6b6b6;
    margin: 1.5em 1.5em 0; }
    .message-list-clear-button.button:hover, .message-list-clear-button.button:focus {
!     background-color: #929292; }
  
  .message-list-sections {
    spacing: 1em; }
--- 901,910 ----
    width: 31.5em; }
  
  .message-list-clear-button.button {
!   background-color: transparent;
    margin: 1.5em 1.5em 0; }
    .message-list-clear-button.button:hover, .message-list-clear-button.button:focus {
!     background-color: #fafafa; }
  
  .message-list-sections {
    spacing: 1em; }
***************
*** 1370,1381 ****
    margin: 5px;
    border-radius: 6px;
    color: #eeeeec;
!   background-color: #a1a1a1;
!   border: 1px solid #2e0000; }
    .notification-banner:hover {
!     background-color: #b6b6b6; }
    .notification-banner:focus {
!     background-color: #929292; }
    .notification-banner .notification-icon {
      padding: 5px; }
    .notification-banner .notification-content {
--- 1370,1381 ----
    margin: 5px;
    border-radius: 6px;
    color: #eeeeec;
!   background-color: #2e3436;
!   border: 1px solid #a1a1a1; }
    .notification-banner:hover {
!     background-color: #2e3436; }
    .notification-banner:focus {
!     background-color: #2e3436; }
    .notification-banner .notification-icon {
      padding: 5px; }
    .notification-banner .notification-content {

Best Regards
 Markus

As the bug still exist in F27, can somebody please add the official fixes from here: https://gitlab.gnome.org/GNOME/gnome-shell-extensions/merge_requests/26

This message is a reminder that Fedora 26 is nearing its end of life.
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bugs or makes them obsolete.

Cloning to Bug #1574407, and assigning version 27 there, because it affects F27 and I cannot change version here (please explain if I should have made it a better way, thx)

Fedora 26 changed to end-of-life (EOL) status on 2018-05-29. Fedora 26
is no longer maintained, which means that it will not receive any
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