I never used to worry about my D-76 going bad, at 1:1 I used it up quick enough. Lately I have been using it at 1:3 and developing a roll at a time so last night after pouring another 4 fl. oz. I gave the bottle a shot of Blow Off brand duster gas and put the cap on. Tonight I noticed the plastic bottle has collapsed a bit, as if some of the air/Blow Off has been absorbed by the developer. The Blow Off ingredient is 1,1-difluoroethane. Wikipedia says it's benign other than being lethal if you huff it.

Could this gas and its absorption by the developer affect the developer's action?