Demonstration of primitive search/replace functionality. The keybindings (which can be configured with custom keymaps) are:

Ctrl-F / Cmd-F
Start searching
Ctrl-G / Cmd-G
Find next
Shift-Ctrl-G / Shift-Cmd-G
Find previous
Shift-Ctrl-F / Cmd-Option-F
Replace
Shift-Ctrl-R / Shift-Cmd-Option-F
Replace all
Alt-F
Persistent search (dialog doesn't autoclose, enter to find next, Shift-Enter to find previous)
Alt-G
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