Consider moving multiple entries out of Main Menu
Current
The Main Menu has multiple entries that users rarely use and probably don't need to be there. For example, 'Firefox Sync' and 'Import and Export' are usually set once and never touched again. 'Text Encoding' is not at all used as far as can be told.
Proposal
These entries should be moved out of the Main Menu and either moved into Preferences or, in the case of 'Text Encoding', removed entirely.