I've used a couple of "smart" TV web browsers, and while I can understand why they are the way they are, they can get quite frustrating to use. It's even more frustrating to use a TV remote as a mouse than it is to use it as a keyboard! Though some TVs are now turning their remotes into (subpar) Nintendo Wii controllers, which partially addresses this issue.
But can I design a smart TV browser that's actually convenient? Maybe one day I'll implement it.
Interestingly DVD remotes had a "angle" button which could apply very nicely here for switching between different stylesheets.
Ideally I'd use the "channel" buttons for scrolling the page, but failing that I'd include (thin) scrollbars in the menu so that when focused you can use the up/down buttons to scroll the page.
You'd be able to navigate into scrolled areas & iframes as submenus, and browser history would be treated as a super-menu.
That supermenu (accessed by pressing "menu"/"back" whilst viewing a page) will allowing you to navigate "tab" history using the left/right buttons, and the up/down to navigate different branches of that history tree.
I imagine most of the browser chrome would be moved to the "homepage" at the root of this history tree, and it's best to replace any toolbar buttons with physical buttons on the remote.
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