SCROLL LEFT/RIGHT buttons no longer recognized in Catalina (BTTv3.157 & 10.15 Beta 4)

Running latest BTT (v3.157) with latest Catalina Beta (#4: 19A512f) the SCROLL LEFT and SCROLL RIGHT buttons (Normal Mouse) are no longer recognized (UP+DOWN work).

Same mouse with same BTT settings (+ version) works fine in Mojave with all scroll buttons recognized (UP/DOWN/LEFT/RIGHT).