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Description

I have a plugin which adds a sub-element into the toolbox which contains an id. When clicking on this element, getToolboxItemById returns null but throws Cannot read properties of null (reading 'isSelectable').

Reproduction steps

1. Create element in toolbox which has an id (or call onClick_ on element that isn't in the toolbox)
2. Error is thrown

Priority

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Stack trace

TypeError: Cannot read propertyies of null (reading 'isSelectable')

Screenshots

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Browsers

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