I worked on a project that implemented a SPA with its own tab-based browsing, including nested iframes for some tabs(!). I worked on another projected that impl

I worked on a project that implemented a SPA with its own tab-based browsing, including nested iframes for some tabs(!). I worked on another projected that implemented a SPA with its own windowing system, because the lead dev thought browser tabs would be too cluttered and users might not know how to use them. (Considering his browser had something like 100 tabs open and he never cleaned them up or opened the existing tabs, I think there was a bit of personal experience colouring his view.) I think the general issue is that there are existing solutions that avoid the downsides associated with this approach, so this seems like re-inventing the wheel. Yes, needless negativity should be avoided, but so should breathless enthusiasm without due diligence.