Created attachment 173593 [details]
Example file from current Writer

Attached file contains two insertions and two deletions. Undo-redo can break if:

* Select from the Track Changes toolbar the Deletions in Margin mode.
In the Manage Changes dialog, select a deletion.
- Accept it. OK, it disappears.
- On the toolbar, Undo. OK, it comes back as deletion.
- On the toolbar, Redo. Bad: the change does not disappear, stays deleted.

Reload, select a deletion.
- Reject it. OK, the text comes back.
- On the toolbar, Undo. OK, the text goes back to be a deletion.
- On the toolbar, Redo. Bad: the text does not come back, stays deleted.

Accepting and rejection insertions, then Undo-Delete works fine.

Another way is to enable the Insertions In Margin mode.

In the Manage Changes dialog select a deletion change.
- Accept it. OK, it disappears.
- On the toolbar Undo. OK, it comes back as deletion. But it is displayed on the margin.
- On the toolbar Redo. Bad: the deletion remains and is not accepted.

Reload, enable Insertions In Margin mode, then select a deletion change in Manage Changes.
- Reject it. OK, the text is no longer deleted.
- On the toolbar Undo. OK, it comes back as deletion. But it is displayed on the margin.
- On the toolbar, Redo. Bad: The deletion remains and is not rejected.

In this mode accepting/rejecting insertion changes works, but after Undo they appear in the text, not margin.

Dear László Németh,
This bug has been in ASSIGNED status for more than 3 months without any
activity. Resetting it to NEW.
Please assign it back to yourself if you're still working on this.

*** Bug 151639 has been marked as a duplicate of this bug. ***