- updated manpage, explained command line keys.

doc/man.org

@@ -81,6 +81,35 @@
   quick  help  window that  can  be  shown  by  hitting ~?~  (if  this
   keybinding has not been customized).
 
+** Command window keys
+
+   The command  window has  a few hardcoded  command keys  to interact
+   with it:
+
+    - the /left/ and /right/ arrow keys move the cursor;
+    - the key /home/ and /end/ move the cursor to the start and end of
+      the input respectively;
+    - /canc/ and  /backspace/ delete  the next and  previous character
+      respectively;
+    - the /new line/ (often called /enter/  key) send the input to the
+      program;
+    - /C-k/ (that is:  "press 'control' and while pressed  press 'k')
+      /kills/ (deletes) the text from the  cursor position to the end of
+      the input previously typed;
+    - press /M-left/ and  /M-right/ (left alt and left  or right arrow
+      together)  to  browse  pages  of  the  suggestion  window;  the
+      suggestion window  is a  window that  holds a  previously inputted
+      data that are compatible with the string the user is typing into
+      the command window;
+    - if suggestions are  gemini URI press /TAB/ to  input the current
+      selected  suggestion   (press  tab  again  to   input  the  next
+      suggestion and so on), otherwise pressing /TAB/ will complete the
+      input with the common prefix of the suggestion window's items;
+    - if suggestion window  is *not* rendered, pressing  /up/ and /down/
+      arrow keys will cycle through input  history, if there is not a
+      suggestion window rendered pressing  /up/ and /down/ will scroll
+      on suggestions.
+
 ** Folders
 
    A folder is an object to groups messages for each timeline an