There are many ways to automate tasks on the web. You can go the programming route and create application dedicated for tasks. However, that needs a big learning curve and dedication to deal with many bugs. Alternatively, you can use tools that are already available. One of those tools is iMacros, which I think is a great tool to automate many of the usual tasks on your browser. Moreover, I’m very grateful that they have free extensions for Chrome and Firefox.
However, using them on the regular browser like Chrome and Firefox is a little heavy on the resource. The latest version of Firefox and Chrome use up much resources even without many tabs, extensions or theme. Moreover, while automating your tasks through iMacros, it is even more prone to using tons of resource, which make automated testing in-efficient. The latest version provides better support for latest tech, but often they are not necessary for every end user or even for testing purposes. Moreover, most of the time while testing they crash or become unresponsive.
A solution to that is using a forked browser; that has cut out much bloat from the main project but still, can run extensions like iMacros. Pale Moon is the browser that I have found that works perfectly and uses much much fewer resources than Firefox while automating tasks and test. Pale Moon is created with efficiency and user choice in mind. This lightweightless allows you to run more applications and expect fewer crashes and not responding behaviours of the heavy browser counterparts.
Pale Moon is a fork of Firefox which uses Firefox rendering engine but strips out many of the features that make it heavy on the resource. The browser should not affect much of your browser experience most of the time and should allow you to browse without any difficulties. If you are an automating task with iMacros, this is even better as this takes a lot less resource and you can have it running it in the background with very less chance of crashing. As a matter of fact, I do not even remember having a crash in the browser while running tasks in iMacros.