Steps to reproduce
Attempt to set heading to none. Alt Cmd 0 once worked for this.
Expected result
heading returned to No Heading emphasis
Actual result
Keystrokes to create heading levels works, to set to no heading does not work. And the option is not settable in the customizable keystrokes list. See screenshot.
Environment
Mac High Sierra, Opera browser latest build 62.0.3331.101!
Additional information
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