Created attachment 47877 [details]
Files and Screenshots demonstration reproduction of the bug

I know this bug has been mentioned on LibreOffice lists, but I could not find it on bugs.freedesktop.org.  This may be a duplicate:

When change-tracking applies to simple deletions that where changes are recorded and shown, the deletion will show as a correct strike-out of text and then suddenly change to a strike-out of the same number of spaces.  It is not possible to recover the original text by rejecting the change.

The attached Zip has a .txt file that describes its comments.

The screen captures show a simple deletion immediately after it is made, and then what it became when the Save button was pressed.  The saved file also had the incorrect deletion in the tracked-changes information.

The before and after files are included, and there is an annotated extract of the change-tracking portion of the content.xml file in the package.

This bug seems related to the one reported at 
<https://bugs.freedesktop.org/show_bug.cgi?id=35966>.  In that bug, the deletion is also altered after the fact, but not quite so quickly and not so dramatically.