Following this change when a user hits `@` and is replying to a topic they
will see usernames of people who were last seen and participated in the topic
This is somewhat experimental, we may tweak this, or make it optional.
Also, a regression in a423a938 where hitting TAB would eat a post you were writing:
Eg this would eat a post:
``` text
@hello, testing 123 <tab>
```
https://stackoverflow.com/a/47822599/17174
Chrome 63 and up start ignoring `autofill="off"`
Per: https://bugs.chromium.org/p/chromium/issues/detail?id=468153#c164
> The tricky part here is that somewhere along the journey of the web autocomplete=off become a default for many form fields, without any real thought being given as to whether or not that was good for users. This doesn't mean there aren't very valid cases where you don't want the browser autofilling data (e.g. on CRM systems), but by and large, we see those as the minority cases. And as a result, we started ignoring autocomplete=off for Chrome Autofill data
So to work around this decision we now explicitly say: autocomplete="discourse"
when we don't want Chrome to randomly fill in addressed (aka. always)
Treating TIFF and BMP as images cause us to add them to IMG tags, this is very inconsistent across browsers.
You can still upload these files they will simply not be displayed in IMG tags.
Fixes composer warnings when: a) mentioning groups ("By mentioning @group, you are about to notify x people...") and b) mentioning users in a PM ("You mentioned @user but they won`t be notified...")
Ember3 is more picky about having a container being destroyed and it's easier to cause exceptions, especially in tests.
This fix has been initially created for an exception occuring in tests when running discourse-code-review and discourse-polls tests at the same time. `getCurrentUser` method body was failing as the container was destroyed.
Original stacktrace:
```
"Error: Assertion Failed: expected container not to be destroyed
at new EmberError (ember:2929:31)
at assert (ember:1793:23)
at Container.lookup (ember:17736:64)
at PluginApi.getCurrentUser (discourse/lib/plugin-api:56:31)
at allowUser (javascripts/discourse/initializers/init-code-review:38:29)
at eval (javascripts/discourse/initializers/init-code-review:78:11)
at eval (select-kit/mixins/plugin-api:86:19)
at Array.forEach (<anonymous>)
at eval (select-kit/mixins/plugin-api:85:44)
at Array.forEach (<anonymous>)"
```
Somehow a plugin or some new Chrome bug is causing its heuristic to detect
our textarea for the composer as a target for address autocomplete
This is likely a chrome bug but this change is very safe regardless.
