We did use react 17 and react-dom 17. It’s possible that there were warnings, but we didn’t encounter any errors.

the reason that you’re encountering the issue is because fragments (the react feature behind reagent’s :<>) was introduced in 16.2.0, so it isn’t present in 16.0.0. If 17.0.1 works despite the warnings, I’d recommend using it. The warnings are coming from react-highlight having out-of-date react dependencies. This is not worrying because react-highlight is only being used for re-frame-10x, and so it doesn’t have any impact on application functionality.

Warnings from NPM like these are common, and can often be resolved or reduced by trimming any unnecessary declared dependencies, and installing the most recent compatible version of any packages that shadow-cljs notices are missing.

If 17.0.1 (version we used) or 17.0.2 (most recent version) don’t work for you, try 16.14.0 (relatively recent version of react 16) instead of going all the way back to 16.0.0.