On Sun, Jul 26, 2020 at 10:15 PM, Adrian Spratt wrote:

press alt-h, then 8, then enter. It’s a toggle.

This works, too.  But there's no need to hit Enter, and doing so will generally result in you putting that into your document.  The display of edit markers comes up/goes away the moment after you've hit that 8 if you use ALT+H,8.

The same is true if you use CTRL+Shift+8, which has the disadvantage of being a triple-key shortcut because of the use of asterisk (shift+8).  The effect of the command is immediate.
 
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Brian - Windows 10 Pro, 64-Bit, Version 1909, Build 18363  

The purpose of education is not to validate ignorance but to overcome it.
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