Not really a Design Tools feature request, but an along-side product request:
We're trying to move some of our faculty away from a popular plagiarism review product's annotation features towards doing all annotating of papers in Canvas' SpeedGrader.
Then it occurred to me that something similar to the Design Tools overlay might do the trick. Something that becomes available or can be minimized while in SpeedGrader. As an example - when using any of the DocViewer annotation features that allow for adding a text comment (point and area annotation automatically open a comment box, while the rest require an additional click to open the comment box), the user could then click on a customizable list of comments from the "Annotation Overlay" which would then copy and paste the selected comment into the comment text box.
Furthermore, if it's a simple "click to copy and paste the contents of this button to the current cursor location" it could also be used for adding longer comments that are regularly used in the right-panel comment section or in rubric comments.
Thank you for your consideration!