Thanks, any testing and feedback is always useful - I'd love to have a ton of devices to test with but it's simply not possible but I do use emulators for some of the major platforms.
A few things that factor into whether something is supported ... I'll try and describe my thinking / process to give you a better idea:
I have limited resources, especially for testing. There are way more browser and device combinations than i can directly support. If I were Amazon where 1% of sales would justify investment it would be different but if something works or not for a 1% segment is best-endeavours.
Typically, I try and use major frameworks and libraries / components and increasingly these target what is known as "evergreen browsers". These are browsers that auto-update to the latest versions and tend to follow the standards. Even major vendors and sites are dropping support for older browsers that consume a disproportionate amount of resources to support.
Often a feature is developed for Chrome / FireFox / Safari / New IE and then you spend 3x as long trying to make it semi-work on an older version of IE or an obscure browser. Now that the market share of these browsers has dropped many people are simply dropping support. That means that the number of people using them will crumble as more and more sites simply won't work.
The other thing I factor in is that although a feature may not work for a browser with 1% market share it doesn't follow that means 1% of users of this site can't use it. Often the share for minority browsers is in niche markets (China especially) which isn't represented in our readership. Also, even if 1% of visitors were using that browser it doesn't mean they don't also have access to other browsers that they can use instead.
I'm working on a new version of the site (ha, I'm always working on a new version) which will change it from a server-side rendered site to a Single Page App with an API - this will make it snappier to use as well as opening the possibility for having installable mobile app versions and different UIs for specific browsers.
In the meantime, I'll do my best to fix any issues if it's minor / easy or make sure compatibility can be built in to the new version.
Thanks again for all the feedback !