I can confirm that when the RadEditor is toggled to full screen the Floating toolbar does not show, but this is reproducible without the right-to-left mode.
I am logging this bug in our database for fixing. Its progress can be tracked in this feedback portal item
in which also, a possible workaround is provided.
As appreciation for this report I am updating your Telerik points.
If you still have issues with the Floating toolbar, please provide further details about what is the result on your end with the workaround placed.
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