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[bertrandda]

Pull Request check-list

To ensure your Pull Request can be accepted as fast as possible, make sure to review and check all of these items:

• If your changes affects code, did your write the tests?
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• Is the linter passing? (npm run eslint on both front/server)
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Description of change

I added rel="noopener noreferrer" for links open in new tab in CalDAV integration page.
I also fix issue #831 by opening Need help links in new tab

[codecov]

Codecov Report

Merging #890 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #890   +/-   ##
=======================================
  Coverage   93.50%   93.50%           
=======================================
  Files         428      428           
  Lines        5607     5607           
=======================================
  Hits         5243     5243           
  Misses        364      364           

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[Pierre-Gilles]

Thanks for this PR :)