big thanks to @insom for telling me that I don't have to buy a new mouse and can easily repair the one I have had for over a decade. it was registering double left clicks when I only pressed once. it was slightly tricky to get at those 3 solder pins sandwiched between 2 PCBs but my beloved Logitech G5 is as good as new! the original microswitch was rated for 10 million clicks and the new one is rated for 20 million, so here's to hoping it lasts another decade!