Text formatting issue in the ticket composer (end-user side)

Hi Zendesk team!

My company that uses Zendesk has got several complaints from our customers about formatting issue in the comment composer from their end. It's not that easy to reproduce it, but as it a customer facing portal, this kind of problem casts a shadow on our reputation as the impression of using Help Center is tightly connected to perception of our company in general. Unfortunately, we can't address this issue and this is purely Zendesk's responsibility to fix it. It's a simple little HTML issue, but it influences us a lot.

Issue:

When an end-user typing a comment, sometimes paragraphs suddenly become light gray. It's not a signature because it appears randomly.

How to reproduce it:

I couldn't find a dependency between the issue and what text should I type to reproduce it, but you can reach me out, and I'll provide some tickets examples (can't attach a screenshot here, there is no possibility to do it here). The important thing here is that the whole text is black before an end-user clicks submit button. Only when the comment is posted, we can see that some paragraphs become gray.