babel-loader has been replaced by the faster
esbuild-loader by default.
If you for some reason need to go back to the previous behavior, you may override the Webpack configuration. Remember that overriding the Webpack configuration works reducer-style, where you get the default configuration in a function argument and you return the modified version of your config.
We provide a compatibility package
@remotion/babel-loader that you can install into your Remotion project and use the function
replaceLoadersWithBabel() to swap out the ESBuild loader with the old Babel one that was in Remotion 1.0
This should not be necessary in general, it is encouraged to report issues regarding the new ESBuild loader.