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I close this panel, open it

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again, and resize the window.

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Why does the same work run twice?

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Each opening adds a new window listener.

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Removing the panel does not remove that listener.

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Closing twice can leave two callbacks

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waiting for the next resize.

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The window keeps the callback.

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The callback keeps the panel it uses.

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Garbage collection frees unreachable objects.

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This panel is still reachable, even

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though you cannot see it.

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00:00:32,300 --> 00:00:33,370
So I need to remove the

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listener when I close the panel.

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How?

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Create an AbortController for each opening and

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pass its signal when adding the listener.

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On close, abort removes that listener.

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Then remove the panel.

20
00:00:48,620 --> 00:00:52,000
You can also remove the listener directly.

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Keep the same function reference

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and the same capture setting.

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A new arrow function will not match the old listener.

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Repeat the same steps after cleanup.

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Now only the open panel reacts.

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This removes one reference path; other references may

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still keep the old panel in memory.

28
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I deleted the panel, but kept paying it to work.

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I accidentally built middle management.