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+MaskRay's random complaints about Language Server Protocol
+
+### Completion
+
+* VSCode sorts `sortText` case insensitively.
+* VSCode only allows length-one strings in `CompletionRegistrationOptions.triggerCharacters` https://github.com/Microsoft/language-server-protocol/issues/138 (closed) Server developers have to work around that. `CompletionTriggerKind::TriggerCharacter` should extend as well.
+* The order of `textEdit` `additionTextEdits` is not specified.
+
+### Formatting
+
+* `firstTriggerCharacter` and `moreTriggerCharacter` should be unified
+
+### Miscellaneous
+
+* `interface Position` uses UTF-16 counting for `character`. https://github.com/Microsoft/language-server-protocol/issues/376
+* `interface Command` (`workspace/executeCommand`) is VSCode centric.
+* `textDocument/implementation` isn't clear. `textDocument/definition` isn't clear when it comes to the difference of declaration/definition.
+* `namespace DocumentHighlightKind` is not a bitmask. `Read` and `Write` cannot coexist.
+* Why can't we get more `namespace SymbolKind` constants sooner? https://github.com/Microsoft/language-server-protocol/issues/344
+
+## Stuff that needs attention
+
+`textDocument/calls` https://github.com/Microsoft/vscode-languageserver-node/pull/420/files
+
+`$ccls/call`
diff --git a/_Sidebar.md b/_Sidebar.md
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   - [[Visual Studio Code]]
 * [[Debugging]]
 * [[Client feature table]]
+* [[LSP]]