fix: recreate dropdown div

[potaracom]

The basics

• I validated my changes

The details

Resolves

Fixes #7571

Proposed Changes

Check if the element(.blocklyDropDownDiv) exists.

Reason for Changes

Closing blockly does not reset the 'div' variable.
Therefore, the createDom method of dropDownDiv is not re-executed.

Test Coverage

I have verified that the drop-down elements are displayed on the second view.

Documentation

Additional Information

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[BeksOmega]

Hiya @potaracom Thank you so much for putting up this PR! I looks great =)

I think this also fails for the tooltip and widget div, could you test for those as well, and fix them if that's the case?

[potaracom]

@BeksOmega
I fixed it.

before

after

[potaracom]

I'm sorry. I will fix test.

[BeksOmega]

Hiya @potaracom ! Thank you for fixing the tests :D I think there might be a simpler solution though. If you remove the call to testOnly_setDiv and its definition does that fix the problem?

If there was another reason (besides the tests) that made you want to remove the global variables, just let me know!

Thank you for your hard work on this :D

[potaracom]

@BeksOmega
There is no reason to remove global variables.
Changed testOnly_setDiv.

[BeksOmega]

This LGTM! Just going to wait for CI to pass and then I'll get this merged!

Let me know if you'd like help finding something else to work on (if you're interested!).

Thank you again for putting up a fix for this =)