When a Site Blocks Text Selection A WordPress site running the All-In-One Security (AIOS) plugin's optional Copy Protection toggle blocked text selection, right-click and copy by setting `user-select: none` on `` and attaching `preventDefault()` listeners for `contextmenu`, `selectstart`, `copy`, `cut`, `paste` and `dragstart` to `document` and `document.body` via `wp-security-front-script.js`. The author used Claude Code with the Chrome DevTools MCP server to trace the listeners to the AIOS plugin and then produced a fix consisting of a competing CSS rule overriding `user-select: none` plus a capture-phase listener that runs before the plugin's bubble-phase handlers, testing it against the live page. When a Site Blocks Text Selection I recently came across a blog post about automated testing best practices. It covered a set of rules, explaining why each should be followed, and a ready-to-use Claude Code skill that enforces those rules automatically when an AI assistant is writing the specs. Exactly the kind of thing a developer might want to copy into their Claude Code setup. But when I went to copy the skill section into my own .claude/skills directory, my mouse stopped responding. Everywhere I tried to click and drag to highlight text, nothing happened. It felt like the page had suddenly locked up. Right-click did nothing either, no context menu. My heart skipped a beat: was this a broken mouse, or was something actually running on my machine, a crypto miner, ransomware quietly encrypting files while the tab just sat there, unresponsive? I opened Chrome's Task Manager Window - Task Manager to check CPU and memory for that tab specifically. A background tab pegged at high CPU could be a sign of suspicious activity, but nothing stood out. My next thought was that something must be wrong with my mouse. I use a Magic Mouse over Bluetooth, and it does occasionally drop out or get flaky mid-click. So I checked System Settings, saw it was connected fine. I also tried clicking around on other tabs and windows, and the mouse was behaving normally. Then I thought maybe the page itself was broken, perhaps a JS error left it half-loaded. But hitting browser refresh didn't help, the mouse was still unresponsive, on that page only. At this point I started to suspect something on the site might be deliberately blocking selection, copying, and right-click. What could it possibly be? Curiosity piqued I pointed Claude Code at the blog post URL, described the copy selection issue, and prompted it to use the Chrome DevTools MCP server https://github.com/ChromeDevTools/chrome-devtools-mcp to figure out what was going on. It pretty quickly found the following: Firstly, user-select: none was set as a CSS rule on