I'm testing my extention for firefox, using temportary installation (at 'about:debugging' page). It has a script file, attached in background, in manifest file. When i make changes in script file (i save them, of course) and refresh extention, it still contains original version of this file. If i delete extention and load it again from same path, it's still contain previous version of background javascript file. I'm checking current file with 'debug' button at the same page. Only when i close and open browser and load extention again, this file changes.