When replies, blank lines are added between paragraphs previous posts (too mutch spaces added)

I have proble of blank lines added in previous posts when answering or forwarding theses posts.

Hi Luc, what version of eM Client are you currently using on your computer, can you please check for the exact version number in Help > About? 
Can you make a screenshot of the issue?

Thank you,
Paul

I confirm this bug on Win 10 emclient v 7.1.30794.0.  

I write new mail by default in plain text.

Reply (and Reply All) generates a lot of blank lines

see: