NestedFilterableMultiselect doesnt stay open on input focus after applying a filter and removing it.

[amirGaouaou]

Detailed description

Describe in detail the issue you're having.
When focusing on the search input, at first the filter list always stays open, if i click again on the search input. Only when I focus out, the list closes.

After applying a filter, the list will open/close after clicking on the search input, this can put the list in a bad state where the search input doesnt work, because the list is closed.

Is this a feature request (new component, new icon), a bug, or a general issue?
Bug
Is this issue related to a specific component?
NestedFilterableMultiselect
What did you expect to happen? What happened instead? What would you like to see changed?
I expect the search input to always work and filter the list.

What browser are you working in?
Chrome
What version of the Carbon Design System are you using?
1.12.3
What offering/product do you work on? Any pressing ship or release dates we should be aware of?
ibmcloud/status
No.

Steps to reproduce the issue

http://cloud.carbondesignsystem.com/?selectedKind=NestedFilterableMultiselect&selectedStory=default&full=0&addons=1&stories=1&panelRight=0&addonPanel=storybook%2Factions%2Factions-panel

1. Click on the input in the NestedFilterableMultiselect
2. List opens, try clicking again on the input, list stays open.
3. Click on one of the items
4. Click on the input, List should open again, click again, list closes.
5. Try searching for an item, list is closed so it doesnt show your search results.

Additional information

• Screenshots or code
• Notes