The switch to storing data in SQLite databases has caused a problem for Firefox users who use the web browser heavily. The databases grow over time and reduce the startup time and responsiveness of the web browser due to fragmentation. This can be largely attributed to the fact that Firefox will not optimize the databases [...]
Speed Up Firefox By Limiting The History
The Firefox web browser will save visited websites for a minimum of 90 days and a maximum of 180 days in the Firefox history by default. The hard limit is set to 40000 websites that are stored in the History. When that limit is reached old history entries will be deleted from the database that [...]

