As always, I would be so grateful for anyone who would like to share ideas or participate in this effort 
My objective here is to have a toolbar button to enable the quick creation of a tooltip which reveals on hover (or optionally on click) and which can contain anything (including but not necessarily limited to HTML and Markdown), and which will most gracefully continue to display the enclosed content even if the component is removed, or when the page is viewed as a published page, and in the absence of any non-core/default plugin or theme component.
I would like the TC to provide the best general compatibility for going forward, leveraging the core Tooltip and/or DModal, or perhaps simply extending or adapting the Footnotes Plugin.
I’ve tested some of the existing theme components and plugins which each provide for specific use cases and each have their own limitations or quirky behaviors, such as not rendering certain types of content correctly, or not useable in mobile, or the Tip container not showing or not adapting to position changes, etc.
I had wanted to make a table showing each existing component/plugin including its respective use case and limitations, but at the moment I don’t have the time, and would certainly welcome any input.