I was getting an Access Violation hard crash in my large, complex app on Windows. It worked fine on MacOS, and it previously worked fine on Windows.
I spent nearly a week trying everything I could think of, including reverting to previous versions of Xojo, previous plugin versions, even an old version of my project that I knew to be working… They all crashed with an Access Violation after my Window.Opening event, somewhere the debugger couldn’t show.
After much hair-ripping, I finally figured out it was a single instance of a DesktopHTMLViewer.
I removed all events from that DesktopHTMLViewer and the Access Violation still happened, it’s mere presence on the window was enough to crash the app.
I removed it, placed a new DesktopHTMLViewer and gave it the same name, then pasted the old object’s events into it, and now the app works without issue.
Now I just want to know what happened. What on earth could corrupt an instance of a DesktopHTMLViewer that would cause an Access Violation crash on Windows but be fine on MacOS?