By default, double-clicking a block opens the Block Editor. But how can a user configure it so that double-clicking a block can open in-place editing instead?
The default behavior is controlled by the system variable BLOCKEDITMODE, which is set to open the Block Editor when double-clicking a block.
The system variable BLOCKEDITMODE controls whether double-clicking a block opens the Block Editor or starts in-place editing.
Setting its value to 0 enables in-place editing on double-click.