The delay on opening quick panel can result in accidental code changes

[rchl]

Summary

I have super+ctrl+o bound to open the project manager panel.
I often press it and start typing immediately to filter the project list but often the first letter ends up in the view instead because the quick panel has not opened yet.
I'm filling this issue to investigate whether it's possible to improve or fix this somehow.
Maybe optimize the speed of opening the panel (I imagine it does quite a bit of file IO, especially with many projects saved).

Expected behaviour

On triggering the project manager the quick panel should open immediately so that all key presses are captured by it.

Actual behaviour

It can take a while to open, resulting in some key presses making changes in the currently open document.

Steps to reproduce

1. Create a key binding like:

    {
        "keys": ["super+ctrl+o"],
        "command": "project_manager",
        "args": {"action": "new"}
    },

2. Save a lot of projects. I have maybe 50.
3. Press the defined keys to open the project manager panel and start typing immediately.

Environment

ProjectManager:

    version: 0.7.19
    installed via Package Control: True

Sublime Text:

    channel: stable
    version: 4101
    platform: macOS
    portable: yes
    architecture: x64