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The picture of the door looks to have polyurethane applied. If this is the case, that’s most likely an oil based finish. If you are trying to apply a latex base interior paint it will ... read more
1) Fiberglass tubs are notorious for getting hairline cracks that usually open up when someone is standing in it with the water running.
2) Also it might be a leak from upstream (plumbing behind the w ... read more