Google had lately made so many significant changes on their apps, services and testing platform services. My favourite had been the reincarnation of the PageSpeed Tools.
Along with going the complex UI/UX changes, the tool now have a way to test page speed on mobile devices too.
Just in case if you are new to the testing platform let me list out things that this tool does, it helps optimise websites performance by suggesting the areas that can be improved. It provides in depth analysis about the best practices that can be implemented to improve the web performance.
After going through some changes as suggested by the tool I was able to get my site to better optimisation and better score.
Wondering how your website perform on optimisation test and see if there is any major or minor changes required, this link will help you for sure Page Speed Insights.