Compare with..Base Revision and Replace with...Base Revision no longer work

[davidhedley]

I am editing files in an SVN repository inside Eclipse.
Recently (last few months) I have noticed that Compare with->Base Revision and Replace with->Base Revision no longer work.
Compare with->Base Revision insists there are no differences between the edited file and the base revision.
Replace with->Base Revision does nothing.
Compare with->Latest from Repository also does not work.
Note:
Team->Revert... does work to replace the file with the base revision version.
Compare with->Revision... and then select a revision does work correctly.

Subclipse 4.3.3.202012181204
Eclipse 2022-03 (4.23.0)

Steps to reproduce

Add a file to an SVN repository in project managed by Eclipse.
Edit the file in Eclipse
Use Compare with->Base revision or Replace with->Base revision

What is the current bug behavior?

With Compare with->Base revision it says "There are no differences between the selected inputs"
With Replace with->Base revision, it says "...has local changes...do you wish to overwrite". If you select "OK", nothing happens.

What is the expected correct behavior?

Differences between the edited version and the base revision