Ooooooh, so glad it works...
At the time being I had to replace quickly the underlying panzoom library, because the previous one seemed not to be maintained anymore. But had no time unfortunately to test it in detail like you did now.
Anyway hopefully others can benefit now from it.
I will release this as soon on NPM...
Copyright OpenJS Foundation and Node-RED contributors. All rights reserved. The OpenJS Foundation has registered trademarks and uses trademarks. For a list of trademarks of the OpenJS Foundation, please see our Trademark Policy and Trademark List. Trademarks and logos not indicated on the list of OpenJS Foundation trademarks are trademarks™ or registered® trademarks of their respective holders. Use of them does not imply any affiliation with or endorsement by them.
The OpenJS Foundation | Terms of Use | Privacy Policy | OpenJS Foundation Bylaws | Trademark Policy | Trademark List | Cookie Policy