Weird rendering of the content within the 'Private Messsage System' Plugin

In the last days I have migrated my site from Joomla 3.* to Joomla 4.*

Now I have some rendering issues within the 'Private Message System' Plugin. Below some details:

The context of my Private Message System Plugin before the migration was this:
Joomla:                               3.10.12
CB:                                      2.9.3+build.2024.09.10.14.21.57.794f9ce0d
Private Message System:   2.9.3+build.2024.09.10.14.21.57.794f9ce0d
Site Template:                     Prostar

the 'result' when writing messages to each other looked like this - which is correct!

 

The context om my private Message System Plugin AFTER  the migration to Joomla 4 was this
Joomla:                              4.4.13
CB:                                     2.10.0+build.2025.02.10.18.59.11.b0d14120b
Private Message System:  2.10.0+build.2025.02.10.18.59.11.b0d14120b
Site:Template:                   Cassiopeia

the 'result' when writing messages to each other looks now like this:

 

Because of some reasons the rendering of the content of the messages will not be separated properly from the author of the message. I have also removed my css overrides in Joomla 4.4.13 installation, but it does not help

Many thanks for your support

Regards

Styling bug that should already be fixed. I recommend updating CB as your install is out of date. Latest CB release is: 2.10.0+build.2025.06.20.17.23.51.16c1e1cee