Bookmarklets are bookmarks with special powers. Effectively, they let you run JavaScript in a browser, which means you can inject JavaScript into a webpage.
The first code block is the bookmarklet itself; create a new bookmark and use this code as the URL. The second code block is the unencoded naked JavaScript; this can be edited then put through the bookmarklet creator found in Useful tools.
Useful for stopping a webpage timing out, which may also log you out.
In the case of this bookmarklet, it reloads a fixed URL (i.e. it doesn’t reload the current URL). It has to be activated from a different tab (a “control” tab), which must be kept open. The new tab (the “refresh” tab) it will create will refresh as per the timer, so if you intend to use the target website, I prefer to open another tab (the “active” tab) and use that one, as that one won’t refresh. I pin the first two in the browser to keep them out of the way and avoid accidentally closing them.
This bookmarklet uses prompts. If you want a bookmarklet with a fixed URL and/or time, change the code below (e.g. u="<https://www.google.com>" or m=5) and recreate the bookmarklet using the bookmarklet creator in Useful tools below.
javascript:(function()%7Bu%3Dprompt(%22URL%3A%20%22)%3B%0Am%3Dprompt(%22Minutes%3A%20%22)%3B%0Aw%3Dwindow.open(u)%3B%0Ai%3DsetInterval(function()%7Bw.location.href%3Du%3B%7D%2Cm*60*1000)%3B%7D)()%3B
u=prompt("URL: ");
m=prompt("Minutes: ");
w=window.open(u);
i=setInterval(function(){w.location.href=u;},m*60*1000);
Useful for videos where controls are disabled.
javascript:(function()%7Bx%3Dprompt(%27Select%20Playback%20Rate:%27)%3Bdocument.querySelector(%27video%27).playbackRate%3Dx%3B%7D)()%3B
x=prompt('Select Playback Rate:');
document.querySelector('video').playbackRate=x;
javascript:(function()%7Bdocument.querySelector('video').playbackRate%3D2%7D)()
document.querySelector('video').playbackRate=2