The canPickMany option of QuickPickOptions appears to have no effect in Theia.
@tetchel Is it still the case?
This is certainly still the case in my testing today, there are no tickboxes when I run Dart: Capture Logs.
Still not supported. Java VS Code uses this for accessors.

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This is certainly still the case in my testing today, there are no tickboxes when I run Dart: Capture Logs.