Everything “off-by-default” is a “Ma’am, in order to refund the faulty transaction, I need you to open settings…” away.
* Is Extend "just another layer"?
Extend, at its core, is a way of bringing navigation/editing to the home position. To do that really well you have to be able to chord modifiers and nav/edit keys easily from the home position. If you can do that with a layer, I'll consider it an Extend-type layer. Many laptop Fn layers, for instance, have only nav/edit and not accessible modifiers so they fail to meet my definition.
I also have multimedia, system and mousing keys in my basic Extend layer. There may be other layers too, such as a NumPad layer and string/symbol/command layers.
An Extend key is a layer modifier that lets you select these layers. You may have both Hold-Extend where you hold the Ext key like a Shift key, and Tap-Extend where you tap it like a dead key. Tap-Extend is best for one-shot stuff like strings/symbols, whereas Hold-Extend is brilliant for nav/edit and NumPad layers.
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* ... Why?
> Living without Extend at this point would seem like some kind of perverse hell imposed as punishment for terrible crimes committed in numerous past lives.
~ SteveP, creator of the Colemak-DH mod
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