Hi there! Thanks for reaching out about Inkpad Notepad showing a grey screen on your laptop after logging in, while it works fine on your iPad and Android device. Let’s get this sorted for you.

Just to clarify a couple of points first:
- Are you accessing Inkpad through a web browser on your laptop or using a dedicated app?
- If it’s a browser, which one are you using? Is it up to date?
- Have you tried any steps already like restarting the laptop or clearing browser cache?

This info will help me tailor the troubleshooting steps for your Windows 10 laptop running WebKit.

Meanwhile, here is a simple guide to start:
1. Clear the browser cache and cookies: Sometimes old stored data can cause display issues like a grey screen. You can do this via the browser settings.
2. Try opening Inkpad in a different browser: For example, if you’re using Edge, try Chrome or Firefox to check if it could be browser-related.
3. Disable browser extensions temporarily: Extensions can sometimes interfere with website loading. Disable them and reload Inkpad.
4. Check for any updates to your browser or Windows: Ensuring your system and software are up to date can resolve compatibility issues.
5. Restart your laptop after performing the above steps before trying again.

If none of those fix it, we may want to look into graphics driver updates or check if Windows Tablet Mode is enabled (which can cause display quirks).

Could you please let me know what browser and steps you have tried? That way, I can guide you through more advanced troubleshooting if needed.