bug(tooltip): matTooltip leaks memory

[mikebolt]

This issue has been reported previously, e.g. in #12644

Reproduction

Steps to reproduce:

1. Visit https://material.angular.io/components/tooltip/overview
2. Take memory snapshot.
3. Wiggle cursor over anything with an on-hover tooltip. (approx 100 times)
4. Take memory snapshot.
5. Repeat 3 and 4 to see an upward trend in memory usage.

Expected Behavior

Memory usage does not increase indefinitely due to toggling tooltip display.

Actual Behavior

It does.

Environment

• Angular: 10.0.1
• CDK/Material: Material
• Browser(s): Chrome 84.0
• Operating System (e.g. Windows, macOS, Ubuntu): gLinux

[crisbeto]

Sounds related to #9109 which we never ended up merging.

[shlomiaz]

Hi, any news on this issue?

[crisbeto]

Is this still a problem under Ivy? My understanding was that it should've resolved it, but I haven't had the time to confirm it.

[shlomiaz]

It was reproduce in v10 by @mikebolt so I guess it is using ivy

[zbagley]

Noting this bug still exists as of today.

[MariaMikhnevich]

Angular Material v19.1.2.
There is still a memory leak. After each show and hide tooltip, the detached elements associated with the tooltip appear in memory, and they are not cleared after the destruction of the element to which the tooltip is attached. They are cleared only after the page is reloaded. This screenshot is an example from the Angular Material v19.1.2 documentation.

Here I opened and closed the tooltip 10 times and you can see an increase in disabled elements associated with the tooltip.

Added to the basic example the ability to delete an element with a tooltip. Here you can see that after deleting a component with a tooltip, it remains in memory as a detached element.

If you delete it without opening the tooltip, then the detached items will not remain in memory.