jquery.fileupload offers the [`pastezone`](https://github.com/blueimp/jQuery-File-Upload/wiki/Options#pastezone) functionality. This functionality is enabled by default and if somebody copy-pastes something into Chrome it will automatically trigger an upload of the content to any configured jquery.fileupload element embedded in the JS.
This implementation triggers some problems:
1. The pastezone is defined globally by default (🙈). So if there are multiple fileupload's on a page (such as in the personal settings) then stuff is going to be uploaded to all embedded uploads.
2. Our server code is not able to parse the data. For example for uploads in the files app we expect a file name which is not specified => Just an error is thrown. You can reproduce this by taking a file into your clipboard and in Chrome then pressing <kbd>CTRL + V</kbd>.
3. When copy-pasting some string from MS Office on the personal page a temporary avatar with said content is created.
Considering that this is anyways was never working at all and causes bugs I've set the `pastezone` to `null`. This mens that upload via copy and paste will be disabled.
Lesson learned: Third-party JS libraries can have some weird details.
If an app is getting enabled in the web UI, an ajax call is now made to
make sure the server still works. If it doesn't, it sends an emergency
app disabling call to disable the breaking app.
When sorting, some browsers like Chrome will lose the scroll position,
possibly because the sorting code is touching the DOM elements.
This fix saves the scroll position before sorting and sets it back
afterwards.
Old code first dit an ajax request to the avatar. Then a new image
object with the same src was created and since we do not cache avatars
yet :( this resulted in 2 sequential requests to the exact same URL
Now if you set the displayname it will first set the placeholder and
then load the avatar in the background. Only once this time!
All IE versions are not able to properly upscale SVG icons unless the
said SVG files contain a "viewBox" attribute, which is not always the
case. Also we cannot guarantee that all third party apps will have this
attribute in their icons.
So for now, app icons will not be displayed in IE instead of broken
ones.
