> It is not Java-specific, but it is common to a few specific Java frameworks as well as at least one of Microsoft's older frameworks (I forget which one).

ASP.NET WebForms has a feature where the Session ID, normally stored in a cookie, is stored in the request URL path instead. This was done back in 1999-2001 to support extremely rudimentary HTTP clients which did not support HTTP Cookies - imagine really prototypical mobile-phone web-browsers or hastily-written shell scripts using CURL.

Fortunately it was disabled by default and the documentation describes why it's a bad idea to use it - and I understand the business reasons for including it - however this design does not break things like multiple-tab browsing: that's just what happens when you have any stateful web-application, regardless of framework.

It's now gone in ASP.NET MVC (where you gave full control over rendered URLs), so that horrid chapter has ended.