3.5.6 adds = signs and garbles URLs

I use phpList to send emails in html, and up to now, it has sent messages that were received with the same text, including no changes in email addresses.

I updated to 3.5.6, and now it adds an = sign after 76 characters, and garbles email addresses. For example, when I send this:

USF United Support Fund for Food Pantries

Many of our students are struggling during this crisis, and the USF Foundation is supporting the ...

(Sorry for cutting this example short, but this board does not let me post anything with more than two links.) I receive this on MS Outlook:

USF United Support Fund for Food Pantries

Many of our students are struggling during this crisis, and the USF Foundation is supporti=
ng the …

Before I updated, there would be no change. I sent this message to a non-Outlook webmail, and got no equal signs, but I did get garbled URLs - which worked, but still recipients will be suspicious, and before, URLs were not changed.

Has anyone experienced this before? I am a novice, and don’t see what in the config or config_extended files could be doing this.

Thank you, Greg McColm

@mccolm You didn’t say from which release of phplist you upgraded but the problem described in an earlier topic might help BUG / Hotmail / phplist 3.2.3