The light seal foam that took me 6 months to stop ignoring

I bought a beat up Canonet QL17 from a flea market in Portland for like $40 and the photos kept coming back with these ugly light streaks on the left side. I assumed it was a shutter issue or maybe a lens problem, so I tore into the shutter speeds and cleaned the glass twice. Turns out after 6 months of frustration and 8 wasted rolls of film, it was just the light seal foam around the film door that had turned to dust years ago. I spent an afternoon with some craft store felt and double sided tape, cut little strips to match the old grooves, and now the camera shoots perfectly clean. The whole time I kept complaining to my buddy who shoots digital and he just said maybe send it to a shop, but I was too stubborn. Has anyone else spent way too long chasing a foggy image problem before realizing it was the cheapest fix possible? What did your camera's light leak turn out to be?