Superglue works great for clean breaks in plastic. If there was any stretching/deformation of the parts the chances of it working plummet. It's no gap filler.
Good ol Duro 5 min epoxy may work out nicely. Similar strength to JB Weld on plastic, little cheaper and is clear instead of dark gray. I've tried "plastic specific" epoxy and found it worked no better, just cost a lot more and stunk to high hell. If you go with any of these three using a sanding board to roughen up the surface where glue is to be applied can help quite a bit.
Whatever you do the break is going to be weaker and likely break again if it gets stressed. Is the slide out tab hollow underneath where you could glue something in place to reenforce it?
I'd probably take it apart, glue it back together for fit, then drill it and support it with steel rods. But I like to overengineer.
--Mc