Chromebook (Chrome browser) copy & paste issue with markdown content

Hello all,
I have the following question.

I have created a file in Nextcloud with normal text and
also a code block with a simple list of checkboxes.

If I copy the content of the code block and paste it into the description area of a deck app card,
it works fine with any browser (tested with Firefox, Edge, Chrome on Win & Linux) .

However, this does not work in Chromebooks using integratet Chrome Browser. (?)
The copy option is offered in the context menu but I cannot paste the copied content anywhere.
I also cannot copy other content of the file (i.e. normal text, outside the code block) and paste it elsewhere.

What am I doing wrong? Is this a Chromebook setting thing?

Cheers Frank