When attachment 179489 [details] is opened in Writer, the lower table changes its cell widths compared to Word and thin extra cells appear on the right side, as seen on attachment 179490 [details].
1, Open attachment 179489 [details] and compare the lower tables cell layout to Word
Seems to have started in 5.3, was good in 5.2, before:
author Miklos Vajna <firstname.lastname@example.org> 2016-09-06 08:16:37 +0200
committer Miklos Vajna <email@example.com> 2016-09-06 12:13:48 +0000
commit 0f2d5db38bac64b665c6e4a127bbbd63a7ed9af5 (patch)
tdf#44986 RTF import: handle \trwWidthA by faking cells
Adding CC to Miklos Vajna
Might be similar to bug 116194 where ~this was fixed for docx.
Another example is attachment 179502 [details] with screenshot attachment 179503 [details] from bug 148550