Current author is not shown when file_storage.save_version_author is set

Seen in 10.9.1 RC2 with
occ config:system:set file_storage.save_version_author --type boolean --value true

• admin adds a 'New text file.txt' and does several edits with files_texteditor
• admin opens the details sidebar and inspects the versions.
• For all versions except for the current version, the author name is shown:
  

Expected behaviour:

• Near the top, under the filename, the line < 1 KB, seconds ago should say e.g. < 1KB, seconds ago, admin

This feature is only important in a shared scenario. When multiple users edit a file, they can see who did the second last change (and before), but they cannot see who did the very last change.

Workaround: one user commits a dummy edit, so that the change in question is listed under Versions.

Reproduce the issue with occ config:system:set file_storage.save_version_author --type boolean --value true, then inspect the details sidebar and Versions behavior in files_texteditor. Done means the current version shows its author near the filename, consistently with older versions, with a regression test covering the display.