Load content script into all tabs, but only if the content script is not already loaded - google-chrome-extension

Question

Problem
My chrome extension needs to inject the content script into all tabs when switched on and then when any new tabs are loaded etc.
By adding the content script to the manifest file I can satisfy the second requirement of having it loaded in newly loaded tabs.
To make it also inject the content script into tabs as soon as the extension is loaded or refreshed (there is no popup), I am using chrome.scripting.executeScript.
Problem is each time the extension is turned off/on or refreshed, the content script is loaded in again and any DOM manipulation from content script occurs multiple times.
So from reading another post, I liked the idea of sending a message to the content script, if I don't get a response (undefined) then I inject the script into this tab, if I do get a response then do nothing.
In my background logs I get this error Unchecked runtime.lastError: Could not establish connection. Receiving end does not exist. which is what I would expect if the content script did not exist, but even when the content script is clearly being loaded, I still get the same error.
Any help greatly appreciated. And maybe this is not even the best approach for this, I am not sure. Ideally I would also want the extension to immediately stop working when it's turned off, but I haven't got around to this problem yet.
Manifest
{
"name": "Text highlighter",
"description": "Text highlighter",
"version": "1.0.0",
"manifest_version": 3,
"background": {
"service_worker": "background.js"
},
"options_ui": {
"page": "options.html",
"open_in_tab": false
},
"content_scripts": [
{
"matches": ["<all_urls>"],
"js": ["content.js"],
"css": [ "styles.css" ]
}
],
"permissions": ["storage", "activeTab", "scripting", "tabs"],
"host_permissions": ["<all_urls>"]
}
self.oninstall = () => {
chrome.tabs.query({}, function(tabs) {
tabs.forEach((tab) => {
chrome.tabs.sendMessage(tab.id, true, (response) => {
console.log('response', response);
if(!response) {
chrome.scripting.executeScript({
target: {tabId: tab.id},
files: ['content.js']
});
chrome.scripting.insertCSS({
target: { tabId: tab.id },
files: ['styles.css']
});
}
});
});
});
};
chrome.runtime.onMessage.addListener((request, sender, sendResponse) => {
console.log('request', request);
sendResponse(true);
return true;
});