IDE xmlresource package breaks the project saving

• Lazarus/FPC Version: Lazarus 2.3.0 (rev main-2_3-949-g02e74c7d81) FPC 3.2.3 x86_64-linux-gtk2
• Operating System: ubuntu 20
• CPU / Bitness: 64

What happens

• I install the 'xmlresource' package from the 'install/uninstall packages' IDE dialog. I recompiled IDE.
• I created new empty project with 1 empty form.
• Then I added 2 new forms (Form2, Form3).
• On saving this new project with 3 forms, I got error-msg per each form.

On pressing Ignore here, I get the same err-msg for Form2, then for Form3. LFM files are not created.