Bugzilla

(In reply to Daniel Holbert [:dholbert] from comment #1)
> Maybe each removal is triggering a notification to be sent to all remaining instances of the image, or something like that?

Hmm, the documentation for `Discard` does suggest that all calls after the first are **supposedly** no-ops in this case:
https://searchfox.org/mozilla-central/rev/a965e3c683ecc035dee1de72bd33a8d91b1203ed/image/imgIContainer.idl#571-575
```
/**
 * If this image is unlocked, discard its decoded data.  If the image is
 * locked or has already been discarded, do nothing.
 */
void requestDiscard();
```

So: given how much time the profile is spending in `Discard`: either we're failing to make those subsequent calls be actually no-ops, or we're doing that part properly and it's just that the one substantial call that we do get takes forever for some reason.

(In reply to Daniel Holbert [:dholbert] from comment #1)
> Maybe each removal is triggering a notification to be sent to all remaining instances of the image, or something like that?

Hmm, the documentation for `Discard` does suggest that all calls after the first are **supposedly** no-ops in this case:
https://searchfox.org/mozilla-central/rev/a965e3c683ecc035dee1de72bd33a8d91b1203ed/image/imgIContainer.idl#571-575
```
/**
 * If this image is unlocked, discard its decoded data.  If the image is
 * locked or has already been discarded, do nothing.
 */
void requestDiscard();
```

So: given how much time the profile is spending in `Discard`: either we're failing to make those subsequent calls be actually no-ops, or we're doing that part properly and it's just that the one substantial call that we do honor (the first Discard call) takes forever for some reason.