Hi, and thank you for asking your question.
Please do this in Firefox now:
Click on the button with three bars at the top-right corner of the Firefox window, and then click on the (?) icon at the bottom of the menu that shows up.
Next, click "Restart with Add-ons Disabled". Firefox will now close, and a popup box will come up.
There, click "Reset Firefox".
After Firefox restarts, please download something first and then check if you are able to clear it out all right.
You may get back to this page after the restart, through your emails received from JustAnswer. If you need any further assistance with this issue, please be sure to reply back using the box below.
Otherwise, if you could kindly take a moment to rate my service at the top of this page, I would greatly appreciate it. Thank you.
Kindly update me on this issue when you can; thank you. If you need more help or if the issue is still not resolved after carrying out the above step, do let me know and I'll continue to follow up further.