Even in 2020 today, emails remain the primary mean of external communication ( at least in my organization). Email signature in such case becomes a powerful marketing channel which you can use to display your Vendor partnership and other marketing communication apart from the usual contact information
Images need to be included, and thats where the problem starts.
The most usual method of including images is to use an HTML signature, with an image element like
<img alt="Logo" style="width:125px; height:auto; border:0;" src="https://yourdomain.com/facebookicon.jpg" width="125" border="0">
Problem is that this image won’t show , till the recipient clicks on “Show Remote images”. Nobody Does that.
Encode it in base64, and embed that in the src, like this
<img alt="facebook icon" style="border:0; height:25px; width:26px;" src=" data:image/png;base64,LONGBASE64ENCODEINGHERE" width="26" height="25" border="0">
Offcourse, your email size is increased, but now your images are shown in the recipient email client- no matter what.
If you are irked by the blocked remote images , this solution may work for you.