At DiversDirect, I ran into a load of issues with website QA because of my browser plugins. Took me a LONG time to figure out the cause — my extensions were throttling page performance. A lot.


Ultimately I wound up uninstalling them and doing all my QA in a Chrome incognito window (as well as naked installs of Firefox and Edge). This reduced page load time 30-50% — from Crisis! to Needs improvement. I only wish we could struggle out of Needs improvement into Fast.
So I wasn’t terribly surprised when I saw the insane impact so many Chrome extensions have on performance (via Hacker Newsletter). I had quite a few of the worst offenders installed on my workstation:
- ColorPick Eyedropper
- Dashlane (hate it, required for work)
- Evernote web clipper
- Ghostery
- LastPass (for personal password management)
- Selenium IDE
- Skype
One of the extensions — not sure which — delayed user interaction by a full five seconds after all the site content was loaded. WTF?
The JavaScript Errors Notifier caused issues, too — because sometimes it reported errors related to my extensions interacting with the page rather than the page itself. I just about drove the developers crazy reporting a bunch of errors (with screenshots!) they couldn’t recreate.

Dev: “No, it isn’t.”
Me: “I have pics.”
Dev: “I can’t recreate it.”
Me: “There is no spoon.”
(Pro tip: DO NOT send screenshots of javascript errors to admin@ or webmaster@ email addresses. NOBODY likes getting those.)
Lesson learned! Now I have a much leaner set of extensions.

Here’s the take-away: when you’re doing QA or UAT in staging or production, make sure your extensions aren’t causing problems. Otherwise you’ll give yourself, and your dev team, massive headaches.
One reply on “User Acceptance Testing, Chrome Extensions, & Performance”
Excellent website. Lots of helpful info here. I am sending it to a few pals ans also sharing in delicious. And naturally, thank you to your effort!| Rosmunda Ari Burra