MacOS – Is it possible to take multiple tabs out of Safari into a new window

You might run a script like this in AppleScript Editor:

tell application "Safari"
    set w to window 1
    set namelist to name of tabs of window 1
    repeat with i from 1 to (count namelist)
        set item i of namelist to (i & " " & (item i of namelist)) as text
    end repeat
    set answer to choose from list namelist with multiple selections allowed
    if answer is false then return
    make new document
    repeat with i in (reverse of answer)
        move tab ((word 1 of i) as integer) of w to beginning of tabs of window 1
    end repeat
    delete tab -1 of window 1
end tell

This moves the current tab and all tabs right of it to a new window:

tell application "Safari"
    set l to tabs of window 1 where index ≥ (get index of current tab of window 1)
    make new document
    repeat with t in (reverse of l)
        move t to beginning of tabs of window 1
    end repeat
    delete tab -1 of window 1
end tell

Both scripts reload each tab though.

I normally just copy the URLs of tabs as text:

set text item delimiters to linefeed
tell application "Safari" to URL of tabs of window 1
set the clipboard to result as text

I can then for example copy part of the lines and run open $(pbpaste).

You need to drag a tab - Safari won't let you drag an entire window into another one. You can hit ⌘T to create a new empty tab (thus making the tab interface visible), then drag your original tab to the other window.