能否自定义Chrome或其他浏览器以在所有打开的标签页运行本地JavaScript文件？如何为Chrome附加JS文件实现页面加载自动执行及Chrome是否存储加载的HTML页面至本地C盘可访问位置？

Great questions! Let's break this down one by one:

Absolutely, you can set up Chrome (or most modern browsers) to run a local JS file across every open tab. Here are two reliable methods:

Method 1: Use a userscript manager (like Tampermonkey) #

This is the most straightforward approach for most users:

• Install the Tampermonkey extension from Chrome's web store
• Click the Tampermonkey icon in your toolbar and select "Create a new script"
• Replace the default template with your local JS code, or use the @require directive to link directly to your local file (note: you'll need to enable "Allow access to file URLs" in Tampermonkey's settings to let it load local files)
• Set the @match rule to *://*/* so the script triggers on every website
• Save the script, and it will automatically run on all existing and new tabs

Method 2: Chrome's Local Overrides (for advanced customization) #

If you want more control over how the script integrates with page content:

• Open Chrome DevTools (F12), switch to the "Sources" panel
• Click the "Overrides" tab on the left, check "Enable local overrides", and select a local folder to store your modified files
• Right-click the page's HTML file in the "Page" tab and choose "Save for overrides"
• Edit the local copy of the HTML file, adding <script src="your-local-script.js"></script> right before the closing </body> tag
• From now on, Chrome will load your modified local HTML version instead of the remote one, automatically running your JS file

Auto-executing JS on page load #

The methods above already cover this, but here's an alternative using a simple Chrome extension (great if you want to package your script for consistent use):

• Create a new folder and add two files:
  1. manifest.json (configure the extension):

     {
       "manifest_version": 3,
       "name": "My Custom Auto-Run Script",
       "version": "1.0",
       "content_scripts": [
         {
           "matches": ["*://*/*"],
           "js": ["your-script.js"],
           "run_at": "document_idle" // Ensures the script runs after the page fully loads
         }
       ]
     }
     

  2. your-script.js (your custom JavaScript code)
• Open Chrome's extensions page (chrome://extensions/), enable "Developer mode", then click "Load unpacked" and select your folder
• The script will now run automatically every time any page finishes loading

Does Chrome store loaded HTML pages locally on the C drive? #

Yes, but it's not designed for manual access:

• Chrome caches HTML, CSS, JS, and other resources to speed up future visits. On Windows, the main cache is located at C:\Users\<YourUsername>\AppData\Local\Google\Chrome\User Data\Default\Cache (with compiled JS stored in the Code Cache subfolder)
• However, cached files use hashed filenames instead of their original URLs, so finding a specific HTML page manually is practically impossible
• Chrome also automatically clears old cache files to free up space, so these files aren't guaranteed to stick around long-term
• If you want to save a specific HTML page locally, your best bet is to right-click the page > "Save as..." and choose a location on your C drive directly

内容的提问来源于stack exchange，提问作者engrgolden