Chrome shows the memory consumption of plugin here : chrome://memory-redirect/

I don't think most users want pop-ups about technical details in browsers. Sublime text is a different story - it's meant for tech folks.

Plugin memory usage tracking is only realistically possible for Chrome where plugins run in a sandbox with a really limited API. Even then, if the plugin manages to allocate memory inside a page's sandbox (for example, by injecting some CSS or JS in there), the reporting will be wrong.

The adblock plus problem is in fact one of those - it injects styles into pages in order to filter ads, which increases the memory footprint of the page. So neither Firefox nor Chrome can tell you 'adblock plus is increasing memory usage by X', because the memory usage is hidden along with everything else owned by the page, not by the addon.

Firefox is adding "add-on compartments" (bug 990729) that allocate separate memory arenas for each add-on. Firefox will be able to use this information to track (most) memory usage for each add-on.

https://bugzilla.mozilla.org/show_bug.cgi?id=990729

It can already measure some parts of add-on memory usage, and you can see this by looking for "add-ons" in about:memory. Bug 990729 will improve the accuracy of the measurements.

There is also this addon (https://addons.mozilla.org/en-us/firefox/addon/about-addons-...) which has a somewhat nicer interface.

Good point, I overlooked the 'injection' part.

Earlier today, and for the first time I recall, Firefox presented me with a slow startup notification. I had some very demanding programs running at the time and knew to dismiss the message without a moments thought. Some users might have responded to the notification.

I didn't click through to the help information at the time, but checking the source it looks like it takes you to https://support.mozilla.org/kb/reset-firefox-easily-fix-most... which suggests a reset. Some users might have gone down that path without recognizing that it would leave them without security related extensions and/or preference changes they had made. Not to mention other less important modifications. Most people don't even keep a log of their changes, making it difficult to get back to what they wanted.

Being informed of conditions that might need your attentions is desirable. However, that doesn't eliminate the need to understand why the conditions arose and what the consequences of different actions would be.

Doesn't the new Internet Explorer do this? I don't really use it that much, but I remember seeing a message suggesting I disable a plugin that was causing slow load times.

Yup, I believe you're right. It only pops up when it detects a problematic plugin. Although I can't remember if it monitors this continuously, or just when you launch IE.

At least in Chrome you sometimes see a notification in the lower left hand corner, something along the lines of "waiting for Adblock extension".