Earlier, if this happened then the button would act as "edit with SPARQL editor" and a new tab would open. So should we make it behave like that?

Won't this be fixed in https://gerrit.wikimedia.org/r/#/c/446491/?

@Smalyshev, the above fix works, but using jQuery's clone() method in the original code will be a better approach. I'd like to make the changes recommended here.
That will remove the need for the above fix and will also fix the parent issue.

Yes the latter option does makes sense! I've changed the implementation to reflect that behaviour.

Should I add an alert or a message that is displayed when a user tries to open a dialog that is already open?

Yes, that works. Thanks!

The resizability feature is a little slow because the height of the dialog body is set to 100%. It works perfectly with a fixed height, but the body size needs to be dynamic. Any suggestions for an alternative to this?

I fixed the next and previous button overflow on the image modal. (https://gerrit.wikimedia.org/r/#/c/416227/)
The titles however are too long to be able to fit within the modal and I'm not sure they're really required as the link to the image is given at the footer of all the image cards.
Perhaps the title can be a single word with a Hyperlink, that would solve the issue.

I'd love to work on this project for GSoC '18.
The project aligns with my skill-set really well and I'm excited at the prospect of working with the MediaWiki team.
I've set up the app locally and for now I'm just making myself familiar with the codebase.
Looking forward to solving the micro-tasks.
Cheers! :)