Number of patches/ Bug Fixes in the last 12 months?

hello together,
I am writing a project about Vaadin-Framework and compare Vaadin with others Frameworks.
I do not know vaadin so well, so i need some Help from the Community.

  1. How many patches have been released in the last 12 months?
  2. How quickly are detected errors will be fixed?

pls answers should have reference!