Thermo pane window seal gasket bulging out

[mark petty]

Need help with this and how to report, is it cosmetic, is it a sign of impending seal failure, what causes it and so on. Thanks

[Rick Cantrell]

Report it as a defect.
What likely caused it is swelling from heat by sunlight.

[Scott Patterson]

Yes, that is a defective window. For some reason it is very common with half round windows like the one in the photo and also with long rectangular windows.

When I find them I say something like this:
"The ______ window has a swollen gasket/seal, this is an indication of a defective windows. The only cure is its replacement".