Does Storyline allow users to right-click hyperlinks to bring up the browser context menu?

You are right that the Storyline player doesn't treat text links like traditional HTML anchor tags as such, so any interactivity you want to have will all need to be managed on the slide as triggers.

If you want to have the web link copied to the user's device clipboard for example you could set up an Execute JavaScript trigger when the element is right-clicked, and use the following JS:

async function copyTextToClipboard(textToCopy) {
  // Check if Clipboard API is available and the writeText method exists
  if (!navigator.clipboard || !navigator.clipboard.writeText) {
    console.error("Clipboard API (writeText) not available.");
    return false;
  }

  try {
    // Attempt to write the text to the clipboard
    await navigator.clipboard.writeText(textToCopy);
    console.log("Copy Successful");
    return true;
  } catch (err) {
    console.error("Failed to copy text: ", err);
    return false;
  }
}

copyTextToClipboard("ADD THE WEB ADDRESS HERE");