Fix for Bug: "Insert blocks by name" creates two undo points when placing a block - #9029
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griffpatch wants to merge 2 commits into
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Fix for Bug: "Insert blocks by name" creates two undo points when placing a block#9029griffpatch wants to merge 2 commits into
griffpatch wants to merge 2 commits into
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…undo point Previously, `BlockCreate` was fired before `onDragStart`. Blockly's `onDragStart` calls `Events.setGroup(true)` internally, creating a new event group for the drag. The `BlockCreate` had no group, so it became a separate undo point from the `BlockMove` fired on drop — resulting in two undo steps: one placing the block at the popup cursor, then another at the drop position. Fix: move the `BlockCreate` fire to after `onDragStart` (in both the new and old Blockly paths). The drag group is still active at that point, so `BlockCreate` and `BlockMove` share the same group and undo together as a single step.
mxmou
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Aug 4, 2026
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The main changes look good and the fix works, but I don't understand some of the added ts-ignore comments.
mxmou
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Aug 4, 2026
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Bug: "Insert blocks by name" creates two undo points when placing a block
Summary
When using the Insert blocks by name addon to place a block, pressing Ctrl+Z once doesn't remove it - instead the block jumps back to where your cursor was when you opened the search popup. A second Ctrl+Z is needed to actually remove the block. Expected behaviour is one Ctrl+Z removes the block entirely.
Bug: "Insert blocks by name" creates two undo points when placing a block
Summary
When using the Insert blocks by name addon to place a block, pressing Ctrl+Z once doesn't remove it - instead the block jumps back to where your cursor was when you opened the search popup. A second Ctrl+Z is needed to actually remove the block. Expected behaviour is one Ctrl+Z removes the block entirely.
Steps to reproduce
Expected behaviour
A single Ctrl+Z removes the block entirely, as it does when dragging a block from the palette.
Root cause
The addon fires a
BlockCreateevent before starting the drag. Blockly's drag start creates a new event group for the drag, leavingBlockCreatein a separate group - so Scratch sees two distinct undo steps: one for the creation (at the popup cursor position), and one for the drop (where you released the block).Fix
Fire
BlockCreateafteronDragStartso it joins the drag's event group.BlockCreateandBlockMovethen undo together as a single step, matching the behaviour of blocks dragged from the palette.