Hi,
Settings, Applications. There is no way to add or delete any needed or unneeded file type. Firefox 55.0.3 opens files name.xlsx in other tab as scrambled text. I need that firefox asks me what to do with this file name.xlsx Firefox already knows that for files name.xls he must ask me what to do.... P.S.Why there is not so simple and needed feature to edit file type list!? Very, very strange.
Please help.
Thanks!
I did not find the right solution from the Internet.
References:https://support.mozilla.org/en-US/questions/1176219
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