Syntax Visualizer stops working until VS2019 is restarted

[vsfeedback]

This issue has been moved from a ticket on Developer Community.

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I've just started playing around with building Roslyn Code Fixes and I'm finding that the Syntax Visualizer window works fine for a while then goes blank, and is not populated again until VS2019 is restarted. Closing the tool window forces the behaviour, but I've also seen it happen when Alt-Tabbing back into VS2019 from another application. No error messages appear in or around the visualizer.

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Original Comments

Visual Studio Feedback System on 9/28/2019, 11:59 PM:

We have directed your feedback to the appropriate engineering team for further evaluation. The team will review the feedback and notify you about the next steps.

Visual Studio Feedback System on 9/30/2019, 00:12 AM:

This issue is currently being investigated. Our team will get back to you if either more information is needed, a workaround is available, or the issue is resolved.

Visual Studio Feedback System on 3/30/2020, 11:42 PM:

Thank you for sharing your feedback! Our teams prioritize action on product issues with broad customer impact. See details at: https://docs.microsoft.com/en-us/visualstudio/ide/report-a-problem?view=vs-2019#faq. In case you need answers to common questions or need assisted support, be sure to use https://visualstudio.microsoft.com/vs/support/. We’ll keep you posted on any updates to this feedback.

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Original Solutions

(no solutions)

[emclain]

I am also having this problem. It's not clear what triggers it, but it usually seems to happen when I'm navigating to a different place in the source file or a different file.

[jonathantorley]

Making a code change seems to bring it back, as does (sometimes) pressing ctrl + space.

[perahoky]

I have the same problem. Syntax Visualizer in VisualStudio v16.8.4 stays empty. Cause/Trigger is unknown, reproducible:

Start solution
Open Code file
Open Syntax Visualizer (or vice versa)
Syntax Visualizer empty
Restart VS probably helps.

[chrhodes]

I'm having this issue - Blank Syntax Visualizer - in 16.9.2 Visual Studio Enterprise

[markolbert]

I'm running into the exact same situation...and, sometimes, ctrl - space and then selecting a valid keyword in context brings it back.

It seems like it dies when the code base gets into a "non compilable" state (i.e., there's a syntax error somewhere among the files that are open).

This is in VS 2019 15.9.3

[TimPickup]

I am having this issue too. After the previous comment about pressing ctrl space.. I realised even just changing Anything made the syntax tree come back for me.. so pressing enter for example to get a new line.

[kjkrum]

Definitely not fixed. Encountered this within minutes of using Syntax Visualizer for the very first time in VS2022.