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Not outside the realm of possibility since they do in fact close off hull breaches or shuttle bays with forcefields. Maybe having something as large as a shield bubble is harmful but small forcefields are OK since they only cover a small area?

My guess would be that a Starship could modify a shield bubble around the ship to contain an atmosphere, but the issue would be that you have the shields up all the time, 24/7. I doubt a ship could do that for more than a few days.

Even if they could afford the shield power requirements 24/7, why spend all that power and the attendant necessity of other life support systems, only to endanger anyone 'outside' when you get into a random fight with a Gorn?

and since they DONT have shields up all the time except for transporters/whatever, then they probably can't run them 24/7... though this is not definitive proof, merely "known facts fit within the theory, but are not true supportive evidence".

it could be convenient for repairing the hull, simply coming out with magnetic boots but without all the environmental suit.

It is also true that a damaged ship could be the one with the least energy reserves to use for this.