[ /k#eys ]

advantage from the 2 or more additional clipboards
• you can define hotkeys instead of the key combinations ( f1-f24  numpadX multimedia keys ins capslock +.. )
→ change i.e. ~lALT & F1:: to f1::

HINT:the cb1 and cb2 (+ cbX ) content is saved until you reload the whole script, in the best case, until the end of your pc session. Adding shortcuts via the gui will empty this clipboards.*

If you intent to use the 2 additional clipboards together with the
Ctrl+C/Ctrl+V clipboard, it's important that you use it in the following order
[ALT]+[F1] ↔ [ALT]+[F2] → [ctrl]+[C] → [ctrl]+[V] than you can paste with ALT + 2 or 1
The reason for the above order:  ALT + 1 /  ALT + 2 overwrides the ctrl+c clipboard

If you have problems with the proper order, use only the 2 additional clipboards
or add another clipboard ↓

If you prefere an advanced clipboard utility, my recommendation (portable) Ditto also an ahk tool

lALT & F1::
send ^c
Clip1 := ClipBoardAll
return

lALT & 1::
ClipBoard := Clip1
send ^v
return

lALT & F2::
Send ^c
Clip2 := ClipBoardAll
return

lALT & 2::
ClipBoard := Clip2
Send ^v
return

lALT & F3::
send ^c
Clip3 := ClipBoardAll
return

lALT & 3::
ClipBoard := Clip3
Send ^v
 return

Note: instead of the long syntax lALT & 1::  you can use  !1:: ( but not !F1:: )