The best one:
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https://apps.apple.com/cn/app/docktime/id508034739?mt=12
Showing the time in 08:20 format.


2nd
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https://apps.apple.com/cn/app/id867539680?mt=12
Free and nice


3rd
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free MacOS Docker clock:
https://apps.apple.com/cn/app/zclock-lite/id1489475245


Its website: https://zclock.xyz/ 
@Lite-Free version