Flaw in BlackMATE theme for evolution mail client

[pkzc]

Expected behaviour

All text in all windows, panels, etc. are readable in evolution.

Actual behaviour

When using the BlackMATE theme, the Description field on the General tab of an evolution calendar entry is shown in white letters on a practically white background, and is unreadable.

Line 24 in /usr/share/themes/BlackMATE/gtk-3.0/gtk-main.css of mate-themes-3.22.24-2.fc39.noarch is this:
@define-color view_color #ECECEC;
This is almost white, changing it to #232323 or similar solves the problem in evolution. It may cause regression somehere else, but I haven't noticed any so far.

Steps to reproduce the behaviour

Double click on a calendar entry to open it.

MATE general version

mate-desktop-1.26.2-1.fc39.x86_64

Package version

mate-themes-3.22.24-2.fc39.noarch

Linux Distribution

Fedora Linux 39

Link to bugreport of your Distribution (requirement)

https://gitlab.gnome.org/GNOME/evolution/-/issues/2649

[lukefromdc]

Unfortunately I cannot work on that, because I have no email accounts that can be accessed other than by webmail. Evolution won't get past the setup screen without one.

[lukefromdc]

Thus I will have to leave this for someone else on the team who can install and run Evolution. I can install it, but I cannot run it past the setup screen without an email account accessable by a dedicated email program. Many non-ad supported and free email accounts (the only kind I have) are webmail-only.

[pkzc]

I think evolution is just fine with that change. The real question seems to me whether it messes something up in some other application.

[lukefromdc]

That change I can test and will, thanks

[lukefromdc]

That created a major problem in a test with gtk3-widget-factory

A test: Do you also get the same issue in adwaita-dark? If you do, the issue is in evolution. If not, we need to identify
the offending widget by name or name of an ancestor so as to restrict the change to evolution only.

[pkzc]

No, Adwaita-dark lends a readable look to evolution all over. That was why I reported to BlackMATE.

But then isn't it a problem with gtk3-widget-factory? It would look quite a bit strange to me if we had two glaring white patches in your picture, and kind of much more natural the present dark background with white or light gray letters.

[lukefromdc]

Gtk3-widget-factory is intended for such jobs as testing themes and learning how GTK's widgets work. To find a "widget chain" or better an application-specific widget name, you need to open evolution with gtk-inspector. You can enable it in dconf-editor, then shift-control-D will bring it up. We REALLY need someone on the team who can run Evolution to work on this!

[pkzc]

I tried it but I am unsure whether this is what is needed:

The object highlighted by the cursor is the offending element in evolution (the Description field on the General tab of an open evolution calendar entry).
evolution had been started with Adwaita-dark but I think it makes no difference if we are after the widget name.

[lukefromdc]

Looks like any textview under EcompEditorEvent (on the road away from my desktop so doublecheck spelling!) Is what we need to explicitly theme here. Doing it that way ensures we are adjusting the color only in Evolution instead of everywhere