Strider cannot climb onto blocks except soulsand from lava while riding them

When I mount a strider with a saddle and try to make it walk out of lava with a warped fungus on a stick, it won't and will stay on the lava as if a block were stopping it from climbing out. This doesn't apply when I walk out of lava on soulsand which works fine. It also doesn't apply when I push a strider without a saddle from lava onto another block