End user-facing error reported when opening a project with restored LSP4IJ editor tabs

[SCWells72]

I sometimes see this error when opening a project that was closed with active editor tabs associated with an LSP4IJ language server definition:

Error while consuming 'textDocument/foldingRange' with language server 'TypeScript Language Server'
org.eclipse.lsp4j.jsonrpc.ResponseErrorException: Request textDocument/foldingRange failed with message: The document should be opened for foldingRanges', file: file:///C:/Users/Scott/dev/projects/IlluminatedCloudTestProjects/df17-with-manifest/force-app/main/default/lwc/demoComponent/demoComponent.js
	at org.eclipse.lsp4j.jsonrpc.RemoteEndpoint.handleResponse(RemoteEndpoint.java:209)
	at org.eclipse.lsp4j.jsonrpc.RemoteEndpoint.consume(RemoteEndpoint.java:193)
	at com.redhat.devtools.lsp4ij.LanguageServerWrapper.lambda$start$4(LanguageServerWrapper.java:314)

@angelozerr provided the following thoughts:

This error comes from when textDocument/foldingRange is called BEFORE a didOpen
When IJ is opening, it opens JavaScript file and as your IJ is indexing, the language server is not started
I did that to improve drasticly the performance of startup
when indexing is finished, I refresh folding
but I think that I have missed the didOpen part in some cases

Overall the error sems to be benign, but it is a bit jarring when opening the project.