When sharing links on social media, it’s ideal to have the title\description\image preview. This can be customized and there are a variety of other rich metadata tricks to play with once a solid foundation is prepared.
The strict minimum for the master picture is 70x70. Your picture is 225x225, which is ok. However, it is recommended to use a picture of at least 260x260. If you still want to use your picture, some of the derivated favicons will not be generated, such as the high resolution tile for Windows 8 / IE 11.
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