Add a minimal resize limit on the preview pane (`.ext-WikiEditor-twopanes-pane2`) to 248px
Bug: T307105
Change-Id: If05376571bb0b223edac48adecbe124e01293c7a
After three slow preview requests, switch to showing a bar at the
top of the preview area that contains a manual 'reload' button.
The manual bar will be hidden when an error message is show, but
re-shown again after the error is dismissed. Closing and
re-opening the preview pane doesn't reset the manual mode.
Bug: T304568
Change-Id: Ia72bd1ceab68fdaed5de53137bd8ac5961db4714
Change from a pseudoelement ::before the left pane, to its own
element. This is so that when we introduce the top manual-reload
bar the blue bouncing loading bar can be shifted down below it.
Also moves the CSS out of TwoPaneLayout.less and into
RealtimePreview.less where it more properly belongs.
Bug: T304568
Change-Id: I540f68d528d92b7db8594d729985e5dad3d90ac1
* Toolbar button to toggle a two-pane layout on and off.
* Resizable bar for the width of the two panes.
* Resizable bar for the edit box height, even when realtime preview is off.
* Only enabled when $wgWikiEditorRealtimePreview = true.
* Fires JS hooks when enabled, resized, and disabled.
Bug: T293347
Change-Id: Id09d44519249c0b7f5c33d48d524b7c92a5a9106
