It has been tried before. One example I can think of immediately is Grail, which was implemented in Python: https://en.wikipedia.org/wiki/Grail_%28web_browser%

It has been tried before. One example I can think of immediately is Grail, which was implemented in Python: https://en.wikipedia.org/wiki/Grail_%28web_browser%29 https://en.wikipedia.org/wiki/Grail_%28web_browser%29 Another is HotJava, which was implemented in Java by Sun: https://en.wikipedia.org/wiki/HotJava https://en.wikipedia.org/wiki/HotJava The results were less than stellar. Neither browser was really comparable to contemporary browsers written in C or C++ in terms of features and performance. Those factors are just too important to overlook, even in the name of security.