The determineIcon() method was expecting attributes to be set which
caused warnings about undefined indices in the error log.
This fix pre-initializes the array with 'directory' and
'isPreviewAvailable' to make them disappear.
Whenever a file is renamed, if the extension changes, the mime type and
preview might change. This fix passes the updated info to the client
that updates it.
- show tooltip when violating naming constraints while typing
- when target filename exists on server fallback to dialog to interrupt the users flow because something unexpected went wrong
- fixes#5062
- also fixes some whitespace and codestyle issues in files js
- uses css selector over filterAttr in touched js files