In the Tabbed users interface Layout tab the Page Columns control is active when the document is in read-only mode. Seems to me it should be disabled.
I confirm it with
Version: 22.214.171.124.alpha0+ (x64)
Build ID: 962b415edb47187737a5f05c4ff3f6724a19c564
CPU threads: 4; OS: Windows 10.0 Build 18363; UI render: Skia/Raster; VCL: win;
Locale: de-DE (de_DE); UI-Language: en-GB
and I agree, that it shouldn't be active