Texlab lsp server exits on unicode letter 1F582

[rommeswi]

Thank you for the bug report

• I am using the latest version of lsp-mode related packages.
• I checked FAQ and Troubleshooting sections
• You may also try reproduce the issue using clean environment using the following command: M-x lsp-start-plain

Bug description

Please see latex-lsp/texlab#1130

Steps to reproduce

Both when I paste 🖂 or use insert-char BACK OF ENVELOPE, the LSP server exits. Deleting the character causes the LSP server again to exit. However, undo after inserting the character leaves the LSP server running.

According to the texlab and emacs developers, the issue arises from lsp-mode sending faulty notifications:

  "jsonrpc": "2.0",
  "method": "textDocument/didChange",
  "params": {
    "textDocument": { "uri": "...", "version": 1 },
    "contentChanges": [
      {
        "range": {
          "start": { "line": 0, "character": 0 },
          "end": { "line": 0, "character": 0 }
        },
        "rangeLength": 0,
        "text": "🖂"
      }
    ]
  }
}```

### Expected behavior

Language server should not crash when inserting unicode symbols.

### Which Language Server did you use?

texlab

### OS

Linux

### Error callstack

_No response_

### Anything else?

_No response_