If you change a global filter, the currently active filter is automatically reset (see below).
Click on the x on the right-hand side of the global filter bar. Another option is to right-click on the group you have filtered and select Clear Global Filter from the context menu.
To change a global filter, right-click on a different group of the same type and set it as global filter. This will automatically deactivate the currently active filter.
While a global filter is active, you can temporarily deactivate it by clicking on the check-box in the global filter bar you see above each filtered list or table.