Somewhat stupid question.

It would be difficult to a number of reasons.

I assume you mean cryogenic storage.

1) The boiling point of LH2 is a lot lower than LOX, different materials
are normally used.

2) Materials allowed for exposure to Hydrogen are differetn than for
oxygen.

For example, organic materials can be exposed to hydrogen, but not to
oxygen.

The main challenge for designing LOX tank: build it with no organics,
all the seals must be metals or ceramics.

The main challenge for designing an LH2 tank: very low temperatures,
much colder than LOX.

Designing a tank for LH2 and LOX storage combines the most difficult
aspects of both problems.