firebase-tools: firestore emulator ui: some collections will not show data, error in console

Some collections will not show data, and will produce an error in the browser console. If I click the collection name in the emulator ui, it will show the doc id of the first document in the URL, but will show no content.

Interestingly my app using the emulator works perfectly fine, and I can even use firebase-admin to query the data, but if I click any of the affected collections, it shows it as if it was empty. Other collections work just fine, and show data as expected.

The total import folder is roughly 12 MB, which I would not consider a large dataset.

Environment info

firebase-tools: 11.0.0

Platform: macOS Monterey 12.3.1 (21E258) (M1 chip)

Test case

As this appears to be somewhat specific to data, I doubt it could be reproduced at will easily, but it is true that some of my other imports with similar structure do not exhibit this error.

Steps to reproduce

run this:

firebase --debug emulators:start --only auth,firestore,functions --import=./path/to/import

Then go to the firestore emulator in the browser, and click one of the affected collection names:

http://XXX.XXX.XXX.XXX:4000/firestore/data/<affected_collection>

Expected behavior

Document list and their content should show in the ui.

Actual behavior

Document list and their content is not showing in the ui, only the + Add document, and to the right the + Start collection and + Add field options, and an error in the browser console:

react_devtools_backend.js:4026 [2022-05-20T08:14:57.612Z]  @firebase/firestore: Firestore (8.8.1): Connection WebChannel transport errored: sr {type: 'c', target: or, g: or, defaultPrevented: false, status: 1}

…and…

GET http://XXX.XXX.XXX.XXX:8080/google.firestore.v1.Firestore/Listen/channel?database=projects%2Fproject-name%2Fdatabases%2F(default)&VER=8&RID=rpc&SID=XXXXXXXXX%3D%3D&CI=0&AID=0&TYPE=xmlhttp&zx=XXXXXXXXXX&t=1 400 (Bad Request)

Relevant part of the output of the logs with --debug flag:

May 20, 2022 10:20:09 AM com.google.net.webchannel.server.v8.BackChannel add
WARNING: Failed to send a new message due to too many pending messagings in the back channel (10001). May need enable flow control.
May 20, 2022 10:20:09 AM com.google.net.webchannel.server.v8.ChannelInternalImpl handle
WARNING: Server fails to send the message, abort the channel!
May 20, 2022 10:20:09 AM com.google.cloud.datastore.emulator.firestore.webchannel.FirestoreV1WebChannelAdapter$FirestoreListenHandler onError
WARNING: [ERROR] NETWORK_ERROR ()