Hello to all!
Clipping highlights/shadows does not show up in Curves tool.
Clip warnings do show up in Levels tool.
Am I missing something? It has worked for me for 10+ years.
Gimp 2.10.36, flatpak update 2024.04.xx
How far back - Gimp 2.10.?? do you remember the clip filter working with curves ?
Kubuntu 22.04 and using a Gimp 2.10.14 (appimage) I get the same as you. Shows with levels but not curves.
edit: I can not go back further than that with 'buntu 22.04 but 'buntu 20.04 and a Gimp 2.10.9 (appimage) and filter -> cut does not work (at least not that version)
Your image needs to be in floating point (16-bit or 32-bit)
Works for me on Ubuntu-MATE 20.04 / GIMP 2.10.36 PPA from Panda Jim (see the highlight in red clipped on the left side?)
[
attachment=11727]
Out of curiosity, about the screenshot below, is it to confuse someone?
[
attachment=11728]
(04-22-2024, 08:43 AM)nbeaudet Wrote: [ -> ] (04-22-2024, 03:40 AM)PixLab Wrote: [ -> ]...
Out of curiosity, about the screenshot below, is it to confuse someone?
Fixed! 
For PixLab, nbeaudet has posted since 2016 - using Parthas Gimp 2.8.14 - now using linux. Not many bother to update their forum profile.
Back to the original question. I still cannot get curves to work with the clip filter
https://i.imgur.com/qIRTQ5P.mp4 kubuntu 22.04 / gimp 2.10.36 (PPA)
and I get the same with Win10 (VM) and a Gimp 2.99.18 (appimage)
...strange....
[attachment=11729 Wrote:rich2005 pid='38894' dateline='1713776597']
(04-22-2024, 08:43 AM)nbeaudet Wrote: [ -> ] (04-22-2024, 03:40 AM)PixLab Wrote: [ -> ]...
Out of curiosity, about the screenshot below, is it to confuse someone?
Fixed!
For PixLab, nbeaudet has posted since 2016 - using Parthas Gimp 2.8.14 - now using linux. Not many bother to update their forum profile.
Back to the original question. I still cannot get curves to work with the clip filter
https://i.imgur.com/qIRTQ5P.mp4 kubuntu 22.04 / gimp 2.10.36 (PPA)
and I get the same with Win10 (VM) and a Gimp 2.99.18 (appimage)
...strange....
Here are this morning's attempts:
Top of screen capture : 16-bit linear floating point
HTH!