This used to work previously but now it looks like the projection buffer is no longer treated as an angularTemplate content type so the editor/LSP doesn't invoke our completions.
The fix would have to somehow modify our content type or generally get editor/LSP to recognize our completion provider as suitable for the content type.
Completions inside projection buffers refers to the scenario of completion at the caret below:
This used to work previously but now it looks like the projection buffer is no longer treated as an angularTemplate content type so the editor/LSP doesn't invoke our completions.
The fix would have to somehow modify our content type or generally get editor/LSP to recognize our completion provider as suitable for the content type.