Is your feature request related to a problem? #
As a new user, I find it confusing to not be able to create cards directly while in a collection. A clear and concise description of what the problem is, e.g. I'm always frustrated when [...].
What solution would you like? #
I believe having a way to pre-select a collection when adding a card to it would make it easier to add cards into it.
What alternatives have you considered? #
Having a button near the share or filter buttons close to the controls of the collection
OR
Having a card-like item in the collection, possibly at the start of it, that serves as a button to add a new card onto it.
Interestingly enough, I added this feature yesterday, which looks very similar to your suggestion! It'll be available soon once we merge to production.