I’m guessing you have no idea. I’ll admit, I don’t either. Nor have I seen my site in most of the 34 browsers which have been used to access it in the last year. It’s not all Chrome, Safari and Edge; from SeaMonkey to Maxthon to Cốc Cốc, you’ll find people are viewing your web site through all sorts of wonderful apps – so can you be sure that it looks OK in all of them?
When your site was first launched, I hope that the designer thoroughly tested it across a range of devices and browsers. But times change. It may have been a few years ago, and the designer could have used code and techniques which were losing support even then. Just this week I went to a site which insisted I install Flash before continuing. No thanks: life’s too short for that. Then there are the browsers which have come along since the site was designed – there’s no way it can have been tested in those. Finally, we have to contend with the ever-growing range of devices and screen sizes being used. Short of a massively expensive audit every few months, it’d be impossible to keep up.
I find that the best approach has to be reactive. In Google Analytics, there are reports called “Technology” and “Mobile”. These can give us a good insight into potential problems. The ‘bounce rate’ column, which I normally don’t like, is our friend here. On either the browser or mobile devices reports, scan down the bounce rate column for any standout high percentages. This indicates that something’s amiss. Don’t forget that you can also see the data by screen resolution, operating system and several other parameters. If you find a 90%+ bounce rate, you might need to take a look using that setup and see what’s putting people off.