Currently the HelpTool action just does this unconditionally:
redirect is not nullable, so the best you could do is set it to an empty string. I am not sure what calling window.open on an empty string does, however, and it may be browser-dependent in any case.
Another option would be to not use the HelpTool at all, and use a CustomAction instead. You can have the configured CustomJS code do whatever you like.
That’s unfortunate but wonder if it would be a useful update in the future.
There are always lot of competing priorities. The most likely route for that to happen quickly would be for an interested new contributor to make a PR for it [1], especially given that CustomAction exists as an alternative.
e.g. making
redirectbe nullable and then conditioning thewindow.openon that would be a straightforward change. ↩︎