Wried cursor behavior with INSERT MULTI CURSOR mode

[JimChengLin]

Describe the bug
In the INSERT mode with single cursor, I can select words with "alt+shift+arrow left/right".
If I duplicate the cursor by "cmd+alt+arrow up/down", then enter the INSERT mode, I can never select words as I do in the normal INSERT mode.

To Reproduce
Steps to reproduce the behavior:

1. Enter NORMAL mode
2. Duplicate cursors
3. Enter INSERT mode
4. Select words by "alt+shift+arrow left/right"
5. See wried behavior(cannot select words)

Expected behavior
I can select words with multi-cursors.

Screenshots
Screenshots are not useful for this issue.

Environment (please complete the following information):

• Extension (VsCodeVim) version: 0.15.7
• VSCode version: 1.25.1
• OS: macOS High Sierra 10.13.6

Additional context
None

[JimChengLin]

Simply disable VSCodeVim temporarily is a good solution.