Do you have a link to what you’re talking about?
Of course you can do a conditional in PHP, it’s just a matter of how you integrated things and if the functions are available between WordPress and bbPress.
What breadcrumb script are you using?
Breadcrumb script: https://wordpress.org/extend/plugins/breadcrumb-navxt/
I’ve integrated it so that bbPress calls WordPress functions, meaning I use get_header and get_footer. All the forum CSS is in my WordPress CSS.
In the WordPress header.php I use that breadcrumb plugin, but obviously on the forum pages I don’t want it to appear.
How about in your WordPress header.php try to wrap the breadcrumb call with something that happens only on bbPress pages. So, if your forum is in a directory called “forum” or something, maybe you could check the REQUEST_URI for the presence of forum. Then you wouldn’t show the breadcrumbs if you were on a forum page. Something like that?
