[@nicolaboscolo Participant 5 years, 5 months ago]

To reproduce the problem I installed a clean wordpress 5.7.1. Then Elementor, bbPress and the test plugin. Then I activated them in the same order. At the moment that I activate the test plugin bbPress menu items literally disappear.
PS: in this configuration I am able access the forum as a user. But when i discovered it on my working site the first time, forum pages were blocked as i described before.