I basically did a new homepage working in front- and backend. I found several "problems" which I have to sort out as the appear both in a vanilla stage branch install with or without your patch applied. There is one thing which I expirenced with applying your patch that works in my installation without the patch.

• go to the frontend
• login as superuser
• in the "user menu" click on "Submit an Article"
• fill in a title and click on the version button

You should than see this error message:
500 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'AND h.ucm_type_id = 1' at line 4 SQL=SELECT COUNT() FROM hmlr9_ucm_history AS h LEFT JOIN hmlr9_users AS uc ON uc.id = h.editor_user_id WHERE h.ucm_item_id = AND h.ucm_type_id = 1 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'AND h.ucm_type_id = 1 ORDER BY h.save_dateDESC LIMIT 0, 20' at line 4 SQL=SELECT h.version_id, h.ucm_item_id, h.ucm_type_id, h.version_note, h.save_date, h.editor_user_id,h.character_count, h.sha1_hash, h.version_data, h.keep_forever,uc.name AS editor FROM hmlr9_ucm_history AS h LEFT JOIN hmlr9_users AS uc ON uc.id = h.editor_user_id WHERE h.ucm_item_id = AND h.ucm_type_id = 1 ORDER BY h.save_dateDESC LIMIT 0, 20 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'AND h.ucm_type_id = 1' at line 4 SQL=SELECT COUNT() FROM hmlr9_ucm_history AS h LEFT JOIN hmlr9_users AS uc ON uc.id = h.editor_user_id WHERE h.ucm_item_id = AND h.ucm_type_id = 1

If you would save the article and edit it again and click on the version button, everthing works.

@waader are you running on postgres? if so not being able to edit a frontend article is a "known" bug. I'm hoping to patch it before 3.4 goes out

No. I did the test with mysql. Postgres will follow ;-).

@waader can you test #4997 please. When that filter package fix gets merged it should fix the bug you reported :)

@test works

I tested with mysql and postgresql and applied additionally #4997. The error on the mysql installation has gone. Under postgresql, content versioning in the frontend doesn´t seem to work at all. There are no error messages but the version box will always be empty no matter how often you change your content. This has nothing to do with your patch.

Closing this for now - as it doesn't really make sense doing this without doing the same thing for the filter class which is so coupled to the input class. Will open a new PR this weekend hopefully.