¿Es posible mantener el acceso directo ⌘ de Chrome para la pestaña de fondo, mientras se usa AppleScript para automatizar la creación de una nueva pestaña?

Creo que esto hará lo que estás pidiendo. Modifiqué su código original para ver qué proceso está al frente en el momento en que se ejecuta , para bifurcarlo y probarlo adecuadamente según las condiciones expresadas en su pregunta mediante el uso de checkModifierKeys*. para ver si ⌘ commandse presionó la tecla cuando Google Chrome es el proceso principal en el momento en que se ejecuta el servicio . * (No tengo afiliación con el blog de Charles Poynton o checkModifierKeys de Stefan Klieme, aparte de haber estado usando este programa durante algunos años sin problemas).

Tal como está codificado, asume que checkModifierKeysestá ubicado en /usr/local/bin/. Modifique según sea necesario.

Ver los comentarios en el if theFrontmostProcessWhenRun is "Google Chrome" then bloque para su flujo lógico .

    on run {input, parameters}

        --  # Get the name of frontmost process at the time the services was run.
        --  #
        --  # This is used later in an if statement block for when if Google Chrome was frontmost process when run
        --  # to check that the value returned from checkModifierKeys was for the command key being pressed.

        tell application "System Events"
            set theFrontmostProcessWhenRun to get name of process 1 where frontmost is true
        end tell

        (*
    When triggering this Service in applications other than Google Chrome, such as TextEdit, the Chrome window opens in the background. This command brings the Chrome window to the foreground:
*)
        activate application "Google Chrome"

        (*
    Converting the selected text to plain text to remove any formatting:
        From: http://lifehacker.com/127683/clear-text-formatting-on-os-x
*)
        set selectedText to input
        set selectedText to (selectedText as text)

        (*
    Removing any line breaks and indentations in the selected text:
        From: http://stackoverflow.com/a/12546965 
*)

        set AppleScript's text item delimiters to {return & linefeed, return, linefeed, character id 8233, character id 8232}
        set plainTextSelectedText to text items of (selectedText as text)
        set AppleScript's text item delimiters to {" "}
        set plainTextSelectedText to plainTextSelectedText as text

        (* Assigning variables: *)
        set baseURL to "https://www.google.com/search?q="
        set finalLink to baseURL & plainTextSelectedText

        (* Opening webpage in Chrome: *)
        (*
    The following tell block creates a new tab, located immediately after the currently open tab, which is what I want to occur.
        From: http://apple.stackexchange.com/questions/271702/applescript-how-to-open-a-link-in-google-chrome-in-a-new-adjacent-tab/271709#271709
*)


        if theFrontmostProcessWhenRun is "Google Chrome" then
            --  # Google Chrome was the frontmost process when the service was run.
            if ((do shell script "/usr/local/bin/checkModifierKeys") as integer) is equal to 256 then
                --  # The command key was pressed when the service was run.
                tell application "Google Chrome"
                    --  # See Note: below.
                    set activeTab to active tab index of front window
                    tell front window to make new tab at after (get active tab) with properties {URL:finalLink} -- open a new tab after the current tab
                    set active tab index of front window to activeTab
                end tell
            else
                tell application "Google Chrome"
                    tell front window to make new tab at after (get active tab) with properties {URL:finalLink} -- open a new tab after the current tab
                end tell
            end if
        else
            --  # Google Chrome was not the frontmost process when the service was run.
            tell application "Google Chrome"
                tell front window to make new tab at after (get active tab) with properties {URL:finalLink} -- open a new tab after the current tab
            end tell
        end if

    end run

Nota: cuando Google Chrome está al frente en el momento en que se ejecuta el servicio y se presiona la tecla, obtiene el actual y lo vuelve a configurar después de crear la nueva pestaña . Esto pretende ser una solución alternativa, ya que es un poco confuso, pero mejor que nada hasta que se pueda encontrar una solución más elegante a un problema.⌘ commandactive tab index