To open the Apple iPhone .heic photos, the Google .webp images or the AOMedia .avif files it's necessary to have the following WIC codecs installed:

Windows 10

.heic

Install both HEIF Image Extensions and HEVC Video Extensions from Device Manufacturer.
Note: if the Device Manufacturer version is not installing try the payed HEVC Video Extensions.

.webp

Install Webp Image Extensions.

.avif

Install both HEIF Image Extensions and AV1 Video Extension.

Older Windows (including older Windows 10)

.heic

Install CopyTrans HEIC/HEIF.

.webp

Install Google WEBP.

.avif

No codec exists.

Attention: after the codec(s) installation please restart FreeVimager and then try again to open your pictures.