Dark mode: Program start and end should be dark, too.

[abose]

Describe the bug

At app start, Tauri will take some time for first render and briefly shows a blank white screen which is bad UX.

For light sensitive users, this is unacceptable, so we are doing this fix on priority.
see details here: https://github.com/orgs/phcode-dev/discussions/2148

Reproduction

start phcode in deark mode, and os in dark mode. A white screen appears briefly.

Expected behavior

no white screen

OS, Browser and Phoenix versions

desktop apps only

logs or debug stack trace if any

Additional context

No response

[abose]

The root cause is underlying Tauri Issue: tauri-apps/tauri#1564 .

It appears that it will be tricky as this is an underlying issue with Tauri which is our main UI engine.
See tauri-apps/tauri#1564 , they have marked it as wont fix and closed it apparently. The hacks described is to hide the window till first render, which may be perceived as slow app boot. This could be a bit tricky to solve, let me try this out and see how bad the load speed is affected.

[abose]

for all the things we tried, the hacs tend to inclrease app start time to about 1 seconds+ on windows, which is unacceptable. The core problem is Tauri core behavior and there is very little we can do now with user space hacks. So we cant proceed with hacks from our en at this time.

I will follow up with Tauri to have a better fix in code for this: https://discord.com/channels/616186924390023171/1343515061913911317/1343515061913911317