Firefox shrinks to smallest size possible when starting and shows error about a massing jar:file when expanded
When expanded, the full error message is: "File not found
Firefox can’t find the file at jar:file:///C:/Program Files/Mozilla Firefox/browser/omni.ja!/chrome/browser/content/browser/browser.xul."
Alla svar (1)
This sounds like something in the installation has become corrupt. You probably want to try re-installing Firefox and see if that helps.