File browser does not show up when operator is executed from a shortcut menu

Question

I'm trying to create an action for the add menu in the video sequencer. I need it to open a file browser so the user can select a file to add. To do this I use ImportHelper, which works great if I trigger my action from the menu at the bottom of the Video Sequence Editor window. However, if I type ShiftA and then select the same action from the menu that pops up, the file browser doesn't show up. Is this a bug in Blender, or am I just missing something?

Here's a slightly modified version of the operator_file_import python template that exhibits this behavior:

import bpy
from bpy_extras.io_utils import ImportHelper
from bpy.types import Operator

class ImportSomeData(Operator, ImportHelper):
    """This appears in the tooltip of the operator and in the generated docs"""
    bl_idname = "sequencer.some_data"
    bl_label = "Import Some Data"

    def execute(self, context):
        print(self.filepath)
        return {"FINISHED"}


# Only needed if you want to add into a dynamic menu
def menu_func_import(self, context):
    self.layout.operator(ImportSomeData.bl_idname, text="Text Import Operator")


def register():
    bpy.utils.register_class(ImportSomeData)
    bpy.types.SEQUENCER_MT_add.append(menu_func_import)


def unregister():
    bpy.utils.unregister_class(ImportSomeData)
    bpy.types.SEQUENCER_MT_add.remove(menu_func_import)


if __name__ == "__main__":
    register()

Answer 1

By looking at the add menu defined in space_sequencer.py it sets layout.operator_context = 'INVOKE_REGION_WIN', this doesn't appear to carry into your menu item.

By setting the operator_context within your menu item method, the sample you provide would appear to work as you expect.

def menu_func_import(self, context):
    self.layout.operator_context = 'INVOKE_REGION_WIN'
    self.layout.operator(ImportSomeData.bl_idname, text="Text Import Operator")