How to view HEIC format pictures in Explorer and the Photos app on Windows 10?

I'm on Windows 10 V1909, 2020-06 Cumulative Update (KB4567512, Build 18363.904). How can I view my HEIC (High Efficiency Image File Format) pictures in Explorer and the Photos app in Windows 10 Explorer?

Explorer shows blank icons instead of the previews. The Photos app gives this message : "We can't open this file".

Even IrfanView (popular Image Viewer) with the necessary plugins installed, would load the files but display only a blank screen.

Microsoft's "HEIF Image Extensions" app in the Microsoft Store (free), which was recommended on various forums, did not solve the issues on my machine.

After much research, Microsoft offers another app in the Microsoft Store called "HEVC Video Extensions".

That second extension has solved the problem. Don't be fooled by the "Video" part in the name. Once installed : Explorer shows previews for HEIC pictures, the Photos app loads them, and even IrfanView now loads them properly.

Sad part : that extension is not free, Microsoft is asking you to pay 0.99 USD for it.