This doesn't fix the issue yet. I am still searching for where in the code mentions (user and room) are being made clickable. @pierre-lehnen-rc do you happen to know that by any chance?

This doesn't fix the issue yet. I am still searching for where in the code mentions (user and room) are being made clickable. @pierre-lehnen-rc do you happen to know that by any chance?

The messages are parsed by this lib:

https://github.com/RocketChat/Rocket.Chat/blob/develop/app/mentions/lib/MentionsParser.js

There are still issues. I think the permissions one might be client side though.

• Major bug importing the settings obj was resolved (correcly? pls check)
• User mentions are clickable
  • user names do not get replaced with real names even when UI_Use_Real_Name is true
• when clicking on channel mentions, a red box with "not allowed" appears
  • console output only has: TypeError: "'name' member of PermissionDescriptor 'microphone' is not a valid value for enumeration PermissionName." which is prob not related
  • server logs indicate it happens when getRoomById is called
• pattern settings are not properly applied to the MentionsParser obj (clickable link ends at umlauts even thought the whole channel name (incl umlaut) was properly added to mentions array)
  • UTF8_Names_Validation is still [0-9a-zA-Z-_.]+ when UI_Allow_room_names_with_special_chars is set

This pull request fixes 1 alert when merging a004a99 into 29eef3d - view on LGTM.com

fixed alerts:

• 1 for Property access on null or undefined

Any errors not related to the import process itself can be left out of the PR and registered as an issue, but do feel free to open a new PR with any fixes you'd like to include.

I separated the fix out into #17776

Also, changing UI_Allow_room_names_with_special_chars doesn't affect UTF8_Names_Validation. @pierre-lehnen-rc do you know where one can implement such a trigger or where one would look for one? If this is fixed, the Umlaut-issue should work, as in app/importer/server/classes/ImporterBase.js, the special chars setting is enabled for the import.

I found the issue. It is that the default UTF8 encoding regex does not contain any non-ASCII chars

A new issue, importing the general channel from slack, has cropped up. This is not handled correctly yet. The problem is, that the general channel in the import slack for me is called "allgmein" it gets imported as <a class="mention-link mention-link--room" data-channel="allgemein">#allgemein</a>. This is prob due to using the name strings and not the names attached to the room objects. Will investigate further.

This pull request fixes 1 alert when merging 978f9ea into 0543346 - view on LGTM.com

fixed alerts:

• 1 for Property access on null or undefined

This pull request fixes 1 alert when merging 4e0055b into 0d2723f - view on LGTM.com

fixed alerts:

• 1 for Property access on null or undefined

This pull request fixes 1 alert when merging adc3a0d into 0d2723f - view on LGTM.com

fixed alerts:

• 1 for Property access on null or undefined

This pull request fixes 1 alert when merging ca13980 into 0d2723f - view on LGTM.com

fixed alerts:

• 1 for Property access on null or undefined

I unfortunately can't lint the commit, as meteor npm run lint returns

TypeError: Cannot read property 'range' of null
npm ERR! code ELIFECYCLE
npm ERR! errno 2
npm ERR! Failed at the Rocket.Chat@3.3.0-develop jslint script.

This pull request fixes 1 alert when merging 305e58e into cae6aeb - view on LGTM.com

fixed alerts:

• 1 for Property access on null or undefined

This pull request fixes 1 alert when merging 8c1a38e into cae6aeb - view on LGTM.com

fixed alerts:

• 1 for Property access on null or undefined

As far as I see it, work is complete. Depends on #17776.

Another Slack's importer issue: #17855

Rebased branch after merge of #17776. Ready to merge now.