Chrome and Firefox are the top 2 web browsers used by ~50% of all web users globally. Here are the some browser App/plugins that I have been using while testing:
#1. Web Developer Toolbar
Download Link: Firefox: Web Developer Toolbar / Chrome: Web developer Chrome
With ‘Web Developer’ Firefox/chrome add-on, you get a lot of web developer options right into your browser which gives you flexibility while testing web applications.
Using this add-on, you can easily verify web elements like H1, H2 title tag attributes, Meta tag information, form details and images. It also enables you to easily display style information for any web element on the web page along with the ability to edit CSS.
View Responsive Layouts Is one more feature of this add-on you can view Mobile, Small tablet and Tablet View in this which will not be accurate but gives an idea or overview
#2. Fox Splitter & Tile Tabs / Tab Scissors
Download Link: Firefox: Fox Splitter | Tile Tabs , Chrome: Tab Scissors
Fox Splitter and Tile Tabs, tabScissors are great add-ons which split your Firefox browser and chrome windows into multiple windows. You can arrange these windows/tiles horizontally, vertically or in a grid – it’s like you are looking at 2 tabs side-by-side in the same Firefox window. Same way Tab Scissors in Chrome
This way, you can easily compare two web pages which proves really helpful when comparing different versions of the same web application or even when your design specifications are available on an internal online portal (like wiki!) and you have the test application open in the other window, these plugins save a lot of your time and effort.
#3. MeasureIt / Page ruler
Download Link: Firefox: MeasureIt, Chrome: Page ruler
MeasureIt and Page ruler are simple and useful add-ons for Firefox/chrome to test height and width of web elements on any web page. It draws a ruler around any web element and shows height and width along the ruler, using which you can test your web application is pixel perfect.
#4. Font Finder (Firefox) / What Font (Chrome)
Download Link: Firefox: FontFinder Chrome: WhatFont
FontFinder and WhatFont allow a user to analyze the font information of any element on a page.
