Short for "Although...But". Typically used to highlight a contradiction or issue when
something seems good or is claimed to be good,
yet you notice a drawback or problem with it.
"I wanna go out tonight, AL;
BT I'm pretty tired."
"That movie was interesting AL;
BT kinda confusing."
"I liked that restaurant, AL;
BT the service was slow." (or "AL;BT the service was slow.")
"The phone looks cool AL;BT battery life sucks." (or "AL;BT the battery life sucks.")