Update does not work while showing table

[CWempe]

This works as expected:

1. select an item in the persistence display
2. click on "update"
3. graph gets drawn
4. select a different item
5. click on "update"
6. new graph gets drawn

This does not work as expected:

1. select an item in the persistence display
2. click on "update"
3. graph gets drawn
4. switch to table
5. table gets shown
6. select a different item
7. click on "update"
8. still the "old" table
9. switch to chart
10. new graph gets drawn
11. switch to table
12. new table is shown (now working!)