Newly created sketches share the same auto-generated name

[91volt]

Describe the bug
When creating a new sketch it automatically gets the name "sketch_monthXXy" (e.g. : sketch_nov03a).
If another sketch is created it will have the same name. This happens because sketches are in a temporary folder until save. Once the first sketch is saved (preserving the generated name) a new sketch is created with the progressive autogenerated name.

To Reproduce
Steps to reproduce the behavior:

1. Go to 'File'
2. Click on 'new'
3. Verify that the newly created sketch name is "sketch_monthXXa"
4. Again go to 'File'
5. Click on 'new'
6. Verify that the newly created sketch name is identical ("sketch_monthXXa")

Expected behavior
I would expect to see the new sketch being named "sketch_monthXXb"

Screenshots
First sketch not saved:

First sketch saved:

Desktop (please complete the following information):

• OS: All
• Version: 2.0.0 beta 12