Add warning for disabling email login regarding strict login check

[mrow4a]

Adds a warning that this config is not effective if strict checking is not enabled. Requires owncloud/core#37569

[codecov]

Codecov Report

Merging #581 into master will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #581   +/-   ##
=========================================
  Coverage     34.79%   34.79%           
  Complexity     1308     1308           
=========================================
  Files            31       31           
  Lines          3719     3719           
=========================================
  Hits           1294     1294           
  Misses         2425     2425           

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[mmattel]

@pako81 @karakayasemi @HanaGemela please rebase and merge.
Referenced core PR owncloud/core#37569 is already merged.

@HanaGemela can this be part/added to the new upcaoming release?

[karakayasemi]

@phil-davis @mrow4a @micbar I just rebased the PR and CI failed. Also, there are several CI fails in nightly jobs. Looks like, one of the recent changes in core or this app, broke tests. Do you have any idea for the reason?

[phil-davis]

@phil-davis @mrow4a @micbar I just rebased the PR and CI failed. Also, there are several CI fails in nightly jobs. Looks like, one of the recent changes in core or this app, broke tests. Do you have any idea for the reason?

You are correct - it got broken with some core acceptance test code changes related to trying to cope with various combinations of LDAP stuff for OCIS testing. When running here in user_ldap it looks like the step:

And user "Alice" has been created with default attributes in the database user backend

now actually ends up creating Alice in LDAP. And then the display name cannot be changed "locally" in oC10.

The problem was not noticed because there is also some problem with pulling osixia/openldap and a lot of CI was failing in the setup steps, even before starting to run any tests. See #590

I will sort out the problem in core...

Update: issue #591 - core PR owncloud/core#37759 has been merged. I an running CI again now to see the result.