All raid frame addons do that if you or others are in combat when they join the group. It’s a rift thing and hasn’t been fixed, nor will it be as resources are no longer allocated.
I had someone criticise my healing in one world event group. I wasn’t even aware I was in a group so serves them right for joining me. I then healed others in the group and watched the gobshite die. Had an extra chuckle when they left the group and immediately rejoined 😀
Type /reloadui, make a macro with /reloadui, or use the reloadui button in gadgets to fix things