How to fix firefox running slow?

Firefox hangs after using it for a long time

Update Firefox

The latest Firefox versions includes improvements in memory usage, especially during long sessions.

Restart Firefox

Firefox may hang if left open for long periods of time. To fix the issue, restart Firefox.

If you regularly leave Firefox open so that you return to where you left off, you may want to use Firefox's Session Restore feature.

Firefox hangs when downloading files or saving images

If Firefox hangs when you attempt to download a file or save an image, try these solutions:

Clear download history

Firefox may hang when downloading files if your download history has grown too large. To clear the download history:

1. Click the Downloads button  on the toolbar, if it's available, or else click the Library  button and click Downloads from the menu.
2. Click Show All Downloads at the bottom of the Downloads panel. The Library window will open.
3. Click the Clear Downloads button at the top of the Library window.
4. Download some sample files to see if the hanging has stopped.

Choose a different download folder

Firefox may hang if the last download folder location (e.g. a shared volume or USB drive) is no longer available. To fix this:

1. Click the menu button  and select Options.
2. Select the General panel.
3. Under Downloads, select Save files to and click the Browse button.
4. In the Choose Download Folder window, choose a new folder location.
5. Close the about:preferences page. Any changes you've made will automatically be saved.

For more solution to fix firefox running slow  Call  +1-856-514-8666.