Cannot view subjects in message list on mobile

This started a few weeks or a month ago. Whenever I open RunBox on my mobile, in the message list, all I can see is sender names. I can’t see subject lines anymore. There is a teeny tiny little scrollbar at the bottom of the screen that I can’t access. Is there a setting I can change? If I switch to inline previews I can get a sense of what the messages are about, but I’m used to seeing the subject line.

I observe a similar but not exactly the same behaviour on (most recent version of) FF under Android 8: the message list is populated, the date, sender and the subject appear. The first line of the email (a preview) does not. After a single tap on the screen the first line/preview appears. Also since few weeks.