This suggestion is intended to be taken in a positive light since you are doing a lot of great work!
When entering a new topic or a reply on the forum, I look for a “Submit” button so that I confidently know that my post will be submitted. Instead, I find a “New Topic” button or a “Reply” button instead. From a developer’s perspective, the button directly indicates what will happen when I click it, but from a users perspective, I want to know that I am submitting the post that I just wrote. I would prefer to only see a word such as “submit”, but it could be combined with the target action such as:
Submit (New Topic)
My expectation is that when I see a button for “Reply”, I will open up a new reply which will probably erase the post that I just wrote.
Hopefully this suggestion is helpful and keep up the great work!