nano: Anchors
3.8 Anchors
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With ‘M-Ins’ you can place an anchor (a kind of temporary bookmark) at
the current line. With ‘M-PgUp’ and ‘M-PgDn’ you can jump to an anchor
in the backward/forward direction. This jumping wraps around at the top
and bottom.
When a line with an anchor is removed, the line where the cursor ends
up inherits the anchor. After performing an operation on the entire
buffer (like formatting it, piping it through a command, or doing an
external spell check on it), any anchors that were present are gone.
And when you close the buffer, all its anchors simply disappear; they
are not saved.
Anchors are visualized in the margin when line numbers are activated.