Created attachment 168972 [details]
Windows 10 Acrylic dark theme by B00marang

Created attachment 168973 [details]
mouse hovering

Created attachment 168974 [details]
LO UI without opening any specific program

Thank you for reporting the bug.

buttons does not go invisible in dark mode 

I can not reproduce the bug present in

Version: 7.0.3.1 (x64)
Build ID: d7547858d014d4cf69878db179d326fc3483e082
CPU threads: 4; OS: Windows 6.3 Build 9600; UI render: Skia/Raster; VCL: win
Locale: en-US (en_US); UI: en-US
Calc: CL

Version: 7.2.0.0.alpha0+ (x64)
Build ID: 761a672d62df1891b9f4f367a499b220ab2b33fa
CPU threads: 4; OS: Windows 6.3 Build 9600; UI render: Skia/Raster; VCL: win
Locale: en-US (en_US); UI: en-US
Calc: CL

Thank you for reporting, Sharigkeen, we appreciate it!

Could you please describe more precisely the steps for reproducing?
As I understand, you tested OS-level dark modes (unrelated to the colour modes in the LibreOffice options). Is that right? Please give more details about:
- Steps for applying the dark mode on Windows
- Steps for applying the dark mode on Linux Mint

You can set the status back to "Unconfirmed" once you have provided the extra information.

This is only for GTK Linux themeing--Acrylic theme of comment 1 is just an os theme to simulate Windows 10 dark mode.  

LibreOFfice has no mechanisim to read actualy UWP os themeing for Windows builds. Though High Contrast a11y themeing like GreyEve do have similar issues with button and menu labeling.

Thank you for clarifying, Stuart!

Confirmed by using the dark mode in GNOME 3.36. Even though the GNOME dark mode uses a dark grey as a base, it is evident that the button text in question has either a poor contrast (in the case of GNOME dark mode) or disappears entirely (for dark modes that use black as a background, as in this bug report's description).

The buttons in question are the right-hand side menus in the tabbed user interface, in all ribbons. The File ribbon happens to have two (File and Help), as well as an extra menu button exhibiting the same issue: Recent Documents.
All other ribbons only have this issue with the right-hand side button of the same name as the ribbon.

To reproduce:

1. Set the OS's appearance to a dark mode
2. In LibreOffice, set the user interface to Tabbed: View > User Interface... > Tabbed

Note that this issue also exist for some dropdowns in at least two other user interfaces: Tabbed Compact and Groupedbar compact.

Changing Blocks to more specific meta bug, and changing the title to more accurately describe the issue.

Version: 7.3.0.0.alpha0+ / LibreOffice Community
Build ID: 1dd4a80fa076bedb3a82821517036bad8dd79857
CPU threads: 4; OS: Linux 5.4; UI render: default; VCL: gtk3
Locale: en-AU (en_AU.UTF-8); UI: en-US
TinderBox: Linux-rpm_deb-x86_64@86-TDF, Branch:master, Time: 2021-07-26_22:41:19
Calc: threaded

Created attachment 179446 [details]
Screenshot in LO 7.3, Write vs Calc

Interestingly, the "Insert" drop-down button (in the "Insert" and "References" tabs) has white text in Writer whereas it has black text in Calc. Also notice the different font (size?) used in the problematic dropdown buttons: it looks bigger.

Could this be a hint at where the issue is? Could someone give pointers to these UI elements, for both Writer and Calc?

Tested with:

Version: 7.3.2.2 / LibreOffice Community
Build ID: 49f2b1bff42cfccbd8f788c8dc32c1c309559be0
CPU threads: 8; OS: Linux 5.13; UI render: default; VCL: gtk3
Locale: en-AU (en_AU.UTF-8); UI: en-US
Calc: threaded

This is a regression as I can't reproduce on:

Version: 6.4.7.2
Build ID: 1:6.4.7-0ubuntu0.20.04.4
CPU threads: 8; OS: Linux 5.13; UI render: default; VCL: gtk3; 
Locale: en-AU (en_AU.UTF-8); UI-Language: en-US
Calc: threaded

I suspect the commit identified by a bibisect will be the same as for Bug 137341.

Bibisect 7.0 Linux.. so not just MacOS commit. 

author	Thorsten Wagner <thorsten.wagner.4@gmail.com>	2020-02-23 
committer	Tomaž Vajngerl <quikee@gmail.com>	2020-03-06 
commit 8d11b953c0a69f4f5eb5ca42dec3812a62d0cd0f (patch)
tree 4061d4c9cd64871154a1fc843eae5cfbb6d22788
parent 4ba09be7e260ce2a79a23465db7b2837422cde30 (diff)
tdf#125532: White text on default/action buttons and selected tabs on macOS

CC Thorsten please check.

*** Bug 141733 has been marked as a duplicate of this bug. ***

This looks like a duplicate of bug 137341

*** This bug has been marked as a duplicate of bug 137341 ***

(In reply to Timur from comment #10)
> Bibisect 7.0 Linux.. so not just MacOS commit. 
> 
> author	Thorsten Wagner <thorsten.wagner.4@gmail.com>	2020-02-23 
> committer	Tomaž Vajngerl <quikee@gmail.com>	2020-03-06 
> commit 8d11b953c0a69f4f5eb5ca42dec3812a62d0cd0f (patch)
> tree 4061d4c9cd64871154a1fc843eae5cfbb6d22788
> parent 4ba09be7e260ce2a79a23465db7b2837422cde30 (diff)
> tdf#125532: White text on default/action buttons and selected tabs on macOS
> 
> CC Thorsten please check.

By commit above, additional colors had to be defined. Obviously there is another part of code which has to be supplemented with definitions for the additional colors in dark mode. This has been done to fix tdf#137341.

For tdf#137341 GTK has been fixed only. Screenshots attached to this issue look like QT. Probably QT has to be fixed too. Currently I am not building for QT, so I am not able to check this further.

(In reply to Thorsten Wagner from comment #13)
> For tdf#137341 GTK has been fixed only. Screenshots attached to this issue
> look like QT. Probably QT has to be fixed too. Currently I am not building
> for QT, so I am not able to check this further.

Thorsten, all screenshots so far have been shared by users reporting using the gtk3 VCL (see Description and comments 7 and 8).

I just tested using kf5 and qt5 VCLs (with the tweak for propagating GTK themes to QT5 apps, described here: https://askubuntu.com/questions/706528/qt-apps-stopped-inheriting-gtk-themes/748186#748186) and I couldn't reproduce the bug. So I believe the issue was always GTK-only and the fix for bug 137341 was enough.