Since the creative mode filter and the normal inventory filter are 2 different systems yet both menus use the same input field, it causes problems.
It seems the design mode inventory has the same issue.
Using the filter of your normal inventory will carry over to the creative mode inventory, but it will also use the old filter "grey-out" system too, together with the new one where blocks disappear from the list.
{F2953}
becomes this in creative mode if you don't remove the filter before clicking this menu
{F2955}
It should look like this in creative mode
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