Query not being cleaned up when on Strict Mode

Intended outcome: When unmounting a component that uses useQuery, it should clean up even when wrapped by Strict Mode.

Actual outcome: Updating the cache on which an unmount component depends, generates a react warning about memory leak.

How to reproduce the issue: https://codesandbox.io/s/nifty-heyrovsky-5cf34 1- Click on “John Smith” and wait for the page to load 2- Click on “Back” 3- Click on “Like” button right by “John Smith” 4- Observe the warning in the console.

Checking on Apollo DevTools, there seems to be more active queries than it should have been after a few times reproducing the issue. Compared to when Strict mode is not active: Versions

@apollo/client: 3.3.15
graphql: 15.4.0
react: 17.0.2
react-dom: 17.0.2
react-router-dom: 5.2.0

[hwillson]

This should be fixed with @apollo/client >= 3.4 - thanks!

[Ralino]

While the warning is gone, I still have the issue that the queries are not cleaned up with @apollo/client 3.4.8 when strict mode is enabled, as shown in this demo: https://codesandbox.io/s/nostalgic-solomon-4stu5

Looking at the active queries with the dev tools, it seems like a query is spawned twice, one with “__typename” queried as well and one without. But only the query with “__typename” is cleaned up. Without strict mode, only a query with “__typename” is spawned (and cleaned up).