Dear Robin,
i have this bug there:

Notice: Undefined variable: countr in …/wp-content/themes/buddyboss-theme-child/bbpress/loop-single-reply.php on line 155

Please help.

[@robin-w Moderator 4 years ago]

that seems to be an error in your buddyboss theme which has amended the loop-single-reply template

loop-single-reply.php in bbpress only has 55 lines.

I would suggest you post this in the buddyboss support forums