Cannot pause or cancel downloads on my android

[CancerAi]

My phone is HuaWei Harmoney3.0.0, when i download things, in my notification bar, there're show "pause" and "cancel" buttons, but its invalid i clicked, what question is it

[tom25519]

I had filed a bug in bugzilla, see: https://bugzilla.mozilla.org/show_bug.cgi?id=1900170