Favorite-folder-area for Open & Save As dialog box windows too small

Hi

Iim using MX Linux 23.2 XFCE; XFCE-version 4.18

Each time when I want to open or save a file the "open"- resp. "save as"-window pops up.
In this window the width of the favorite-folder is too small and I cannot see the foldernames completely.
(Foto here: https://imgur.com/a/IOT01CJ )
Of course I can widen this area to see the foldernames completely.
But I have to do this every time because the widened favorite-folder-area is not saved.

Affected programs:
Softmaker Office
XnView Multi platform
Ksnip
Master PDF Editor
VLC
KeePassXC

No problem with
LibreOffice
Inkscape
Thunar

Please note: changes of the complete window size are stored, but not the favorite-folder-area.

How can the widened favorite-folder-area being kept / saved permanently?

Many thanks!