Based on the bisexual infinity∞ symbol with the engagement⚬ unicode, this was first created in 2015 with a gradient and more elaborated/complicated, including more &lt;non-binary&gt; gender symbols.
Own work, from https://vikingqueer.tumblr.com/post/146891861327/png-version-of-the-symbol-i-made-for; https://system-lgbt.tumblr.com/post/176490300628/amp
Kautr