在网页的任何地方，您都可以这样做：

anywhere in a web page, you could do this:

<script>
if(console) {
    console.log("Firebug is installed and running!");
} else {
    alert("Firebus either isn't installed, or isn't running.");
}
</script>

如果您特别想检查Firebug，那就不完美了，因为它可能会报告其他浏览器上存在Firebug例如Chrome，因为他们的开发者工具也使用与Firebug相同的控制台对象。如果你真的只需要检查Firebug，那么你也可以添加浏览器检测以确保你在Firefox中。

Not perfect if you specifically want to check for Firebug, because it could report that Firebug exists on other browsers such as Chrome, since their Developer Tools also use the same console object as Firebug. If you really need to only check for Firebug, then you could also add a browser detection to make sure you're in Firefox.