Warning -- Rollup 'sourcemap' option must be set to generate source maps.

[Skenvy]

Using this as is I was getting a warning during rollup (!) [plugin typescript] @rollup/plugin-typescript: Rollup 'sourcemap' option must be set to generate source maps. until I found rollup/plugins#1805 which suggests using --configPlugin 'typescript={compilerOptions:{sourceMap:false}}' --sourcemap as options to rollup to fix it, which has been the only thing I've found that has fixed it after a while of searching. Probably worth adding to the package.json's scripts.