Many users requested this feature, which would make espanso capable of expanding rich text (text with formatting, such as bold, center, italic, images).
A typical use case would be in email signatures.
I don't know if you're interested in ideas around this, but if you are... I was thinking a "markdown" type might be a way to do this with plaintext YAML. Essentially, strings of type "markdown" could be processed before being inserted. Making markdown a type prevents every string from being needlessly processed too.
Mocked up example:

I second a request for Markdown processing support for rich text!
@lyonsinbeta @pseudomichael I was thinking about HTML, but indeed markdown would be better for the user. We'll probably end up supporting both, as we need to copy HTML content in the clipboard, so we need a markdown to HTML compiler for Rust (which luckily, seems to exist: https://github.com/johannhof/markdown.rs)
Given the interest, I'll move this issue up in priority, so that hopefully we get a POC in the next release :)
Experimental support coming in the next release!

You'll be able to specify the rich text both as markdown and HTML as you suggested:
- trigger: ":rich"
markdown: "This *text* is **very rich**!"
- trigger: ":ric2"
html: '<p>But <span style="color: #ce181e;"><span style="font-size: x-large;">this</span></span> one is <span style="color: #81d41a;"><span style="font-family: Arial, sans-serif;">even richer</span></span>!</p>'
Cheers :)
This has been fixed in the new release! See: https://github.com/federico-terzi/espanso/releases
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This has been fixed in the new release! See: https://github.com/federico-terzi/espanso/releases