Release 2021.07 - Hard feature freeze now effective

Dear RIOTers,

We've created the 2021.07 release branch, so we are now officially in
feature freeze. This means from now only bugfixes will be backported to
the `2021.07-branch`. If anyone has any bugfixes or documentation
improvements that they feel should be part of this release please let me know.

New features can still be merged into master during this period.

The test tracking issue of release candidate 1 [1] is opened. Help with
testing and resources for the testing is as always very welcome. Most of
the testing is automated [2], but some stuff still needs to be run manually.
So if you want to help, please put your name after the corresponding item
in the linked issue to streamline the testing efforts.

Thanks all for the awesome work!

Best regards,



It seems like we are just about there.

All who are interested, please feel free to adapt the draft release notes generated by @aabadie very nice release note generator!