Un-hide :open-editor

It can be used in normal mode as well, and it's nice to have it discoverable.
Fixes #3235.

doc/help/commands.asciidoc

@@ -60,6 +60,7 @@ It is possible to run or bind multiple commands by separating them with `;;`.
 |<<messages,messages>>|Show a log of past messages.
 |<<navigate,navigate>>|Open typical prev/next links or navigate using the URL path.
 |<<open,open>>|Open a URL in the current/[count]th tab.
+|<<open-editor,open-editor>>|Open an external editor with the currently selected form field.
 |<<print,print>>|Print the current/[count]th tab.
 |<<quickmark-add,quickmark-add>>|Add a new quickmark.
 |<<quickmark-del,quickmark-del>>|Delete a quickmark.
@@ -657,6 +658,12 @@ The tab index to open the URL in.
 ==== note
 * This command does not split arguments after the last argument and handles quotes literally.
 
+[[open-editor]]
+=== open-editor
+Open an external editor with the currently selected form field.
+
+The editor which should be launched can be configured via the `editor.command` config option.
+
 [[print]]
 === print
 Syntax: +:print [*--preview*] [*--pdf* 'file']+
@@ -1158,7 +1165,6 @@ How many steps to zoom out.
 |<<move-to-start-of-next-block,move-to-start-of-next-block>>|Move the cursor or selection to the start of next block.
 |<<move-to-start-of-prev-block,move-to-start-of-prev-block>>|Move the cursor or selection to the start of previous block.
 |<<nop,nop>>|Do nothing.
-|<<open-editor,open-editor>>|Open an external editor with the currently selected form field.
 |<<prompt-accept,prompt-accept>>|Accept the current prompt.
 |<<prompt-item-focus,prompt-item-focus>>|Shift the focus of the prompt file completion menu to another item.
 |<<prompt-open-download,prompt-open-download>>|Immediately open a download.
@@ -1409,12 +1415,6 @@ How many blocks to move.
 === nop
 Do nothing.
 
-[[open-editor]]
-=== open-editor
-Open an external editor with the currently selected form field.
-
-The editor which should be launched can be configured via the `editor.command` config option.
-
 [[prompt-accept]]
 === prompt-accept
 Syntax: +:prompt-accept ['value']+

qutebrowser/browser/commands.py

@@ -1625,8 +1625,7 @@ class CommandDispatcher:
             self.on_editing_finished, elem))
         ed.edit(text, caret_position)
 
-    @cmdutils.register(instance='command-dispatcher', hide=True,
-                       scope='window')
+    @cmdutils.register(instance='command-dispatcher', scope='window')
     def open_editor(self):
         """Open an external editor with the currently selected form field.