Question: Which browsers are compatible with both?
SQL: SELECT T3.name FROM web_client_accelerator AS T1 JOIN accelerator_compatible_browser AS T2 ON T2.accelerator_id   =   T1.id JOIN browser AS T3 ON T2.browser_id   =   T3.id WHERE T1.name   =   'CACHEbox' INTERSECT SELECT T3.name FROM web_client_accelerator AS T1 JOIN accelerator_compatible_browser AS T2 ON T2.accelerator_id   =   T1.id JOIN browser AS T3 ON T2.browser_id   =   T3.id WHERE T1.name   =   'Fasterfox'