Henlo buddy, your script didn't work for me, so I fixed it. Works for me now. I also changed lemmy.world to sh.itjust.works so beware.

Here's my final one:

// ==UserScript==
// @name         Lemmings Fix
// @version      1.0
// @description  Redirect to your local Lemmy instance
// @author       @lemmy.world/u/soy
// @match        https://*/c/*
// @icon         https://join-lemmy.org/static/assets/icons/favicon.svg
// ==/UserScript==

const localLemmy = "sh.itjust.works";
var isLemmy =
  document.head.querySelector("[name~=Description][content]").content ===
  "Lemmy";

if (isLemmy) {
  // Get URL info
  var splitUrl = location.href.split("/");
  var instanceUrl = splitUrl[2];
  var community = splitUrl[4];
  var localizedUrl =
    "https://" + localLemmy + "/c/" + community + "@" + instanceUrl;

  // Create redirect button if not on local
  if (instanceUrl !== localLemmy) {
    var zNode = document.createElement("div");
    zNode.innerHTML = "Open in local instance";
    zNode.setAttribute("id", "localizeContainer");
    // add styles to the button embedded
    zNode.setAttribute(
      "style",
      "cursor: pointer; padding: 16px; background-color: red; border-radius: 10%; border-width: 3px; border-style: solid; padding: 3px; z-index: 10;max-width:200px;position:fixed;top:0;right:0;"
    );
    zNode.addEventListener("click", onLocalize);
    document.body.appendChild(zNode);
  }
}

function onLocalize() {
  window.location.replace(localizedUrl);
}

Hah, just came here to suggest an improvement, but the script has already transformed completely while I was gone :D

Excellent work!

i made a new userscript for submitting forms with Ctrl + Enter. Is that something you'd find useful?

// ==UserScript==
// @name         Lemmy Form Submit with Ctrl+Enter
// @version      1.0
// @description  Submit forms with Ctrl+Enter in Lemmy instances so you don't have to click the button every time you want to post something.
// @author       God (https://sh.itjust.works/u/god)
// @match        https://*/post/*
// @match        https://*/comment/*
// @icon         https://join-lemmy.org/static/assets/icons/favicon.svg
// ==/UserScript==

var isLemmy =
  document.head.querySelector("[name~=Description][content]").content ===
  "Lemmy";

if (isLemmy) {
  // Define a global variable to keep track of the currently focused textarea.
  var currentFocusedTextarea = null;

  // Function to attach focus and blur event handlers to all textareas.
  function attachEventHandlers() {
    document.querySelectorAll("textarea").forEach((textarea) => {
      if (!textarea.dataset.ctrlEnterHandled) {
        textarea.dataset.ctrlEnterHandled = true;

        // Check if this textarea is currently focused
        const wasFocused = document.activeElement === textarea;

        textarea.addEventListener("focus", function () {
          currentFocusedTextarea = this;
        });

        textarea.addEventListener("blur", function () {
          currentFocusedTextarea = null;
        });

        // If this textarea was focused, blur and re-focus it to ensure event handlers get triggered
        if (wasFocused) {
          textarea.blur();
          textarea.focus();
        }
      }
    });
  }

  // Attach a keydown event handler to the entire document.
  document.addEventListener("keydown", function (event) {
    // If Ctrl + Enter is pressed
    if (event.ctrlKey && event.key === "Enter") {
      // If a textarea is focused and contains text
      if (
        currentFocusedTextarea &&
        currentFocusedTextarea.value.trim() !== ""
      ) {
        // Your submit logic here
        handleSubmit(currentFocusedTextarea);
      }
    }
  });

  function handleSubmit(textarea) {
    // find the closest type="submit" button and press it.
    textarea.closest("form").querySelector('[type="submit"]').click();
  }

  // Call the function initially to cover textareas that exist when the page is first loaded.
  attachEventHandlers();

  // Observe the document for changes and reattach event handlers when new textareas are added.
  const observer = new MutationObserver(function (mutations) {
    mutations.forEach((mutation) => {
      if (mutation.type === "childList") {
        attachEventHandlers();
      }
    });
  });

  observer.observe(document.body, { childList: true, subtree: true });
}

i made a new userscript for submitting forms with Ctrl + Enter. Is that something you'd find useful?

// ==UserScript==
// @name         Lemmy Form Submit with Ctrl+Enter
// @version      1.0
// @description  Submit forms with Ctrl+Enter in Lemmy instances so you don't have to click the button every time you want to post something.
// @author       God (https://sh.itjust.works/u/god)
// @match        https://*/post/*
// @match        https://*/comment/*
// @icon         https://join-lemmy.org/static/assets/icons/favicon.svg
// ==/UserScript==

var isLemmy =
  document.head.querySelector("[name~=Description][content]").content ===
  "Lemmy";

if (isLemmy) {
  // Define a global variable to keep track of the currently focused textarea.
  var currentFocusedTextarea = null;

  // Function to attach focus and blur event handlers to all textareas.
  function attachEventHandlers() {
    document.querySelectorAll("textarea").forEach((textarea) => {
      if (!textarea.dataset.ctrlEnterHandled) {
        textarea.dataset.ctrlEnterHandled = true;

        // Check if this textarea is currently focused
        const wasFocused = document.activeElement === textarea;

        textarea.addEventListener("focus", function () {
          currentFocusedTextarea = this;
        });

        textarea.addEventListener("blur", function () {
          currentFocusedTextarea = null;
        });

        // If this textarea was focused, blur and re-focus it to ensure event handlers get triggered
        if (wasFocused) {
          textarea.blur();
          textarea.focus();
        }
      }
    });
  }

  // Attach a keydown event handler to the entire document.
  document.addEventListener("keydown", function (event) {
    // If Ctrl + Enter is pressed
    if (event.ctrlKey && event.key === "Enter") {
      // If a textarea is focused and contains text
      if (
        currentFocusedTextarea &&
        currentFocusedTextarea.value.trim() !== ""
      ) {
        // Your submit logic here
        handleSubmit(currentFocusedTextarea);
      }
    }
  });

  function handleSubmit(textarea) {
    // find the closest type="submit" button and press it.
    textarea.closest("form").querySelector('[type="submit"]').click();
  }

  // Call the function initially to cover textareas that exist when the page is first loaded.
  attachEventHandlers();

  // Observe the document for changes and reattach event handlers when new textareas are added.
  const observer = new MutationObserver(function (mutations) {
    mutations.forEach((mutation) => {
      if (mutation.type === "childList") {
        attachEventHandlers();
      }
    });
  });

  observer.observe(document.body, { childList: true, subtree: true });
}

If someone wouldn't mind throwing this up on, say, userforks or similar, that would be great.

I wish lemmy instances had an indicator for if that instance is lemmy instead of using the url.