Weird right alignment/flipping issue with some applications in Kubuntu 20.04

The issue I am facing is that some apps (I suspect GTK apps) are right aligned.

The issue with gimp (snap package):

Flatseal:

Then there's the issue with cursors in dialogboxes that start from the right-side by default:

Solution 1:

You need to change your desktop theme back to the default Breeze theme. The current GTK theme you're using is producing this unwanted behaviour.

1. Open the Settings app in KDE Plasma:

   

2. Navigate to Appearance → Global Themes:

   

3. Select the Breeze theme:

   

4. Tick the Use desktop layout from theme option:

   

5. Click on Apply:

   

6. Log out and log in again.

That's it!
Good Luck!