Keyboard focus issues with angle and note fields

[mxmou]

To reproduce the issue, create the following stack in both Scratch and spork:

In Scratch:

• When clicking the "point in direction" angle input or navigating to it using the keyboard, it receives focus and I can immediately start typing.
• If I click the first block's input and press Tab twice, the third block's input is focused, as expected.

In spork:

• When clicking the "point in direction" angle input or navigating to it using the keyboard, the dropdown has keyboard focus, even though it isn't possible to interact with it using the keyboard. To actually type into the number field, I have to click it again or press Shift+Tab.
• If I click the first block's input and press Tab twice, the project title in the menu bar is focused.

The same happens if the "point in direction" block is replaced with a "play note" block from the Music extension.