Many applications unusable on KDE/Wayland/HiDPI: is this specific to KDE?

I am finding out that many applications are just unusable on the KDE/Wayland combination on HiDPI displays that require scaling, because the don’t do any scaling at all resulting in unreadable fonts/icons.

A couple of examples for those willing to test:

  • scilab (from upstream)
  • the tangram browser (flatpak, from flathub)

The problem seems to involve mostly electron apps (but still I have electron apps that are totally usable, e.g. teams) and/or that require some gnome runtime.

These applications appear to be totally insensitive to the setting of GDK_SCALE or GDK_DPI_SCALE.

In order to try to identify the issue and send appropriate bug reports, I would like to first find out if this problem is specific to KDE or also present in other desktops and principally in Gnome.

Would someone on Gnome using an HiDPI display be so kind to let me know if Tangram is usable, and does font scaling possibly trying it with as a test website?

Scaling an application requires the application to support it otherwise it beomes a mess.

It is likely because the developers of the package has not created the apps with HiDPI in mind.

Usually you will have to talk to the developers and have them to implement support for HiDPI.