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* `copy_selection_on_prev_line`
* `extend_char_left`
* `extend_char_right`
* `extend_line_down`
* `extend_line_up`
* `move_char_left`
* `move_char_right`
* `move_line_down`
* `move_line_up`
* `no_op`

runtime/help/copy_selection_on_prev_line.txt

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+`copy_selection_on_prev_line`
+
+Copies the current primary selection to the first previous line long enough to accomodate it.
+
+--- Examples ---
+
+The selection is copied from line 1 to line 2.
+┌───────────────────────────┐     ┌───────────────────────────┐
+│ This is text on line 1.   │ --> │ This is text [on line 1]. │
+│ This is text [on line 2]. │     │ This is text [on line 2]. │
+└───────────────────────────┘     └───────────────────────────┘
+
+The selection duplication skips line 2 because it is too short.
+┌──────────────────────────────────┐     ┌──────────────────────────────────┐
+│ This is a longer line of text.   │     │ This is a longer li[ne of t]ext. │
+│ This is a shorter line.          │ --> │ This is a shorter line.          │
+│ This is another lon[ger lin]e.   │     │ This is another lon[ger lin]e.   │
+└──────────────────────────────────┘     └──────────────────────────────────┘

runtime/help/extend_char_left.txt

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+`extend_char_left`
+
+Extending version of `move_char_left`.

runtime/help/extend_char_right.txt

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+`extend_char_right`
+
+Extending version of `move_char_right`.

runtime/help/extend_line_down.txt

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+`extend_line_down`
+
+Extending version of `move_line_down`.

runtime/help/extend_line_up.txt

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+`extend_line_up`
+
+Extending version of `move_line_up`.

runtime/help/move_char_left.txt

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+`move_char_left`
+
+Moves all cursors 1 character left, removing any selections.

runtime/help/move_char_right.txt

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+`move_char_right`
+
+Moves all cursors 1 character right, removing any selections.

runtime/help/move_line_down.txt

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+`move_line_down`
+
+Moves all cursors 1 line down, removing any selections.
+Repeating this will remember the vertical position of the cursors, even when moving across shorter lines.
+
+--- Examples ---
+
+The cursor remembers its vertical position, even after moving across the shorter line.
+┌────────────────────────────┐     ┌────────────────────────────┐     ┌──────────────────────────────┐
+│ This is a longer l[i]ne.   │     │ This is a longer line.     │     │ This is a longer line.       │
+│ Shorter line.              │ --> │ Shorter line.[]            │ --> │ Shorter line.                │
+│ This is another long line. │     │ This is another long line. │     │ This is another lo[n]g line. │
+└────────────────────────────┘     └────────────────────────────┘     └──────────────────────────────┘

runtime/help/move_line_up.txt

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+`move_line_up`
+
+Moves all cursors 1 line up, removing any selections.
+Repeating this will remember the vertical position of the cursors, even when moving across shorter lines.
+
+--- Examples ---
+
+The cursor remembers its vertical position, even after moving across the shorter line.
+┌──────────────────────────────┐     ┌────────────────────────────┐     ┌────────────────────────────┐
+│ This is a longer line.       │     │ This is a longer line.     │     │ This is a longer l[i]ne.   │
+│ Shorter line.                │ --> │ Shorter line.[]            │ --> │ Shorter line.              │
+│ This is another lo[n]g line. │     │ This is another long line. │     │ This is another long line. │
+└──────────────────────────────┘     └────────────────────────────┘     └────────────────────────────┘

runtime/help/no_op.txt

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+`no_op`
+
+Does nothing. Use this to disable default keybinds.