Often videos on the Learn page at the University of Edinburgh are teeny-tiny for a reason which escapes most of us. Create a bookmark with the location set to the contents of bookmarklet.js and if you click it on a Learn page, it will maximise the space given to the videos. Alternatively, open up DevTools and paste it into the command line.

bookmarklet.js

javascript: function resize() {
  document.querySelectorAll(".kalturawrapper").forEach((wrapper) => {
    wrapper.parentElement.style.width = "100%";
    wrapper.parentElement.style.height = "unset";
    wrapper.parentElement.style.maxWidth = "1000px";
    wrapper.parentElement.style.maxHeight = "unset";
    wrapper.style.width = "100%";
    wrapper.style.height = "unset";
    wrapper.style.maxWidth = "unset";
    wrapper.style.maxHeight = "unset";
    wrapper.style.paddingTop = "calc(1080 / 1920 * 100% + 25px)";
  });

  document.querySelectorAll(".kalturawrapper > iframe").forEach((element) => {
    element.style.position = "absolute";
    element.style.top = "0";
    element.style.bottom = "0";
    element.style.left = "0";
    element.style.right = "0";
  });
}
resize();