Important fixes

• Fix Spyder hanging at startup on Linux when started in a terminal in background mode.
• Fix appeal/sponsor Spyder message being shown at every startup.
• Fix error that prevented mouse clicks in Spyder to work on the Windows Subsystem for Linux.
• Avoid crashes at startup from faulty/outdated external plugins.
• Fix Spyder installer not being able to finish installation due to Start Menu entry error in some Conda installations.
• Fix Spyder installer not installing the right Spyder version (6.0.0 vs 6.0.0rc2)
• Fix Binder instance with example workshop project from being non-responsive.
• Fix errors related to unmaximazing panes and layout changes.

Full changelog: https://github.com/spyder-ide/spyder/blob/master/changelogs/Spyder-6.md