Typically, the supported mode of RadEditor for Mobile devices is the Mobile RenderMode (Phone Layout). Using the Lightweight or Classic in mobile devices is not supported as there are many native limitations regarding the editable iframe that cannot be solved technically from web components' end.
The client-side .focus() method is a jQuery method that is not implemented in RadEditor. The RadEditor API exposes the .setFocus() method. However, this should not bring up the keyboard as in mobile devices it is a matter of security restriction—keyboard will open up only if there is a user interaction. Opening the keyboard programmatically could be considered as violation of some internal rules, which are not implemented in RadEditor, but in the native mobile browser applications.
I am not sure how this is implemented so to work with the old version. Can you provide a sample code, how focusing is implemented so to check that out on my end and see if there is indeed a regression bug?
As for recovering from edit mode in Phone Layout, you need to setup the ToggleScreenMode tool which will close the editing mode and restore from fullscreen, which will show the page as designed.
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