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@vcastroi
Last active March 17, 2024 18:22
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// create a bookmark and use this code as the URL, you can now toggle the css on/off
// thanks+credit: https://dev.to/gajus/my-favorite-css-hack-32g3
javascript: (function() {
var elements = document.body.getElementsByTagName('*');
var items = [];
for (var i = 0; i < elements.length; i++) {
if (elements[i].innerHTML.indexOf('* { background:#000!important;color:#0f0!important;outline:solid #f00 1px!important; background-color: rgba(255,0,0,.2) !important; }') != -1) {
items.push(elements[i]);
}
}
if (items.length > 0) {
for (var i = 0; i < items.length; i++) {
items[i].innerHTML = '';
}
} else {
document.body.innerHTML +=
'<style>* { background:#000!important;color:#0f0!important;outline:solid #f00 1px!important; background-color: rgba(255,0,0,.2) !important; }\
* * { background-color: rgba(0,255,0,.2) !important; }\
* * * { background-color: rgba(0,0,255,.2) !important; }\
* * * * { background-color: rgba(255,0,255,.2) !important; }\
* * * * * { background-color: rgba(0,255,255,.2) !important; }\
* * * * * * { background-color: rgba(255,255,0,.2) !important; }\
* * * * * * * { background-color: rgba(255,0,0,.2) !important; }\
* * * * * * * * { background-color: rgba(0,255,0,.2) !important; }\
* * * * * * * * * { background-color: rgba(0,0,255,.2) !important; }</style>';
}
})();
// ---------------------------------------------------------
// another bookmarklet to display the elements Id on screen, some of them do display themselves on top of others
javascript: (function () {
var styleEl = document.getElementById("css-id-labels-hack");
if (styleEl) {
styleEl.remove();
const elems = document.querySelectorAll(".css-idlabel-dbg");
[...elems].forEach((elem) => {
elem.remove();
});
return;
}
styleEl = document.createElement("style");
styleEl.id = "css-id-labels-hack";
styleEl.innerHTML =
"div.css-idlabel-dbg{ text-shadow: 3px 3px 4px white; position: fixed; background-color: rgba(0,255,0,0.4) !important; outline: 0px !important; color: rgb(0, 0, 0) !important; padding: 2px !important;} ";
document.body.append(styleEl);
const elems = document.querySelectorAll("[id]");
[...elems].forEach((elem) => {
const divroot = document.createElement("div");
divroot.setAttribute("class", "css-idlabel-dbg");
divroot.textContent = "#" + elem.id;
elem.insertAdjacentElement("afterbegin", divroot);
});
})();
@rokhimin
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rokhimin commented Sep 4, 2019

image

@kennethvandenhoven
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Hi vcastroi,

You said:
// create a bookmark and use this code as the URL, you can now toggle the css on/off

How do you accomplish this?

Regards,
Kenneth

@dermyhughes
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dermyhughes commented Sep 4, 2019

For Chrome.

  • Bookmarks > Bookmark Manager

  • Click on the 3 dots on the top right. Choose Add new bookmark.

  • Give it a name.

  • Paste the above code from line 3 down. Don't paste the comments. It should start with javascript: (function() {

  • Save. To use it, simply use the bookmark on any page.

@DJviolin
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DJviolin commented Sep 4, 2019

Thank You! It works on most of the sites, except Github. Strange.

@kennethvandenhoven
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Great! Thank you both!

@AdnanCutura
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AdnanCutura commented Sep 4, 2019

extra tip

You can, in Mozilla Firefox, add a keyword while adding a bookmark, for example add keyword check, and you will be able, just typing the check in the URL and hitting the enter, to see the results.

tag

@mutheusalmeida
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Thank You! It works on most of the sites, except Github. Strange.

I think that's because it is a gist.

@Conrad777
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Thanks for this... it is very handy!!

I wanted to change the colors around and ended up having to change the code in 2 places cause sometimes the string check didn't work anymore... so I simplified the code a bit. I only tested in Chrome, so maybe there is a good reason why you did it your way, but for what it is worth here is my amended solution:

javascript: (function() {
  const element = document.querySelector('#test-layout-styles');
  if (element) {
    document.head.removeChild(element);
  } else {
    const style = document.createElement('style');
    style.id = 'test-layout-styles';
    style.innerHTML = `
          * { background-color: rgba(255,0,0,.2); }
          * * { background-color: rgba(255,0,255,.2); }
          * * * { background-color: rgba(0,255,255,.2); }
          * * * * { background-color: rgba(255,255,0,.2); }
          * * * * * { background-color: rgba(0,255,0,.2); }
          * * * * * * { background-color: rgba(0,0,255,.2); }
          * * * * * * * { background-color: rgba(255,0,0,.2); }
          * * * * * * * * { background-color: rgba(255,255,0,.2); }
          * * * * * * * * * { background-color: rgba(0,255,255,.2); }
    `;
    document.head.appendChild(style);
  }
})();

@andersdn
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andersdn commented Sep 5, 2019

If you wanted to make it shorter (and dont mind using a single color) you could fill the array n number of times, that way you don't have to do each line of css manually

javascript: (function() {
  const element = document.querySelector('#test-layout-styles');
  const cssString = '* { background-color: rgba(0,255,255,.2);!important}';
  if (element) {
    document.head.removeChild(element);
  } else {
    const style = document.createElement('style');
    style.id = 'test-layout-styles';
    style.innerHTML = Array(20).fill().map((i,k) => '* '.repeat(k) + cssString).join(';\r\n');
    document.head.appendChild(style);
  }
})();

@nutchy
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nutchy commented Sep 5, 2019

@ta-riq
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ta-riq commented Sep 9, 2019

Nice tricks 🎉,It's same as this extension https://chrome.google.com/webstore/detail/pesticide-for-chrome/bblbgcheenepgnnajgfpiicnbbdmmooh

Thats really great....

Now I _dont have to write_ this every time in my stylesheet.

@gazdagergo
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Just copy the code into this tool and your bookmarklet is ready for use: https://chriszarate.github.io/bookmarkleter/

@rmaksim
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rmaksim commented Dec 19, 2019

javascript: (function() {
  const element = document.querySelector('#test-layout-styles');
  const bg = (c) => `{background-color: rgba(${c==1||c==3||c==5?255:0},${c==2||c==3||c==6?255:0},${c==4||c==5||c==6?255:0},.2) !important;}`;
  if (element) {
    document.head.removeChild(element);
  } else {
    const style = document.createElement('style');
    style.id = 'test-layout-styles';
    style.innerHTML = Array(40).fill().map((i, k) => '* '.repeat(k+1) + bg((k%6)+1)).join('\r\n');
    document.head.appendChild(style);
  }
})();

@iliyaZelenko
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Why there construction javascript: ? what does it do and what is it called?

@vcastroi
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vcastroi commented Jan 1, 2020

@hitao123
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thanks

@vcastroi
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made a small change to add a div that displays the Id of the elements on the page, was helpful on a recent site I had to debug, so I'll save it here

image
looks like this ^ some labels are still had to read, maybe this will be on its own separate Bookmarklet later

javascript: (function () {
  var styleEl = document.getElementById("css-layout-hack");
  if (styleEl) {
    styleEl.remove();
    const elems = document.querySelectorAll(".css-name-dbg");
    [...elems].forEach((elem) => {
      elem.remove();
    });
    return;
  }
  styleEl = document.createElement("style");
  styleEl.id = "css-layout-hack";
  styleEl.innerHTML =
    "div.css-name-dbg{   text-shadow: 3px 3px 4px white; position: fixed;    background-color: rgba(255, 255, 255, 0) !important;    outline: 0px !important;    color: rgb(0, 0, 0) !important;    padding: 2px !important;} * { background:#000!important;color:#0f0!important;outline:solid #f00 1px!important; background-color: rgba(255,0,0,.2) !important; }    * * { background-color: rgba(0,255,0,.2) !important; }    * * * { background-color: rgba(0,0,255,.2) !important; }    * * * * { background-color: rgba(255,0,255,.2) !important; }    * * * * * { background-color: rgba(0,255,255,.2) !important; }    * * * * * * { background-color: rgba(255,255,0,.2) !important; }    * * * * * * * { background-color: rgba(255,0,0,.2) !important; }    * * * * * * * * { background-color: rgba(0,255,0,.2) !important; }    * * * * * * * * * { background-color: rgba(0,0,255,.2) !important; }";
  document.body.append(styleEl);
  const elems = document.querySelectorAll("[id]");
  [...elems].forEach((elem) => {
    const divroot = document.createElement("div");
    divroot.setAttribute("class", "css-name-dbg");
    divroot.textContent = "#" + elem.id;
    elem.insertAdjacentElement("afterbegin", divroot);
  });
})();

@vcastroi
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I've added the id as a separate bookmarket, not sure if I can add an onclick copy-to-clipboard function to the label, maybe I'll try that latter
image

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