[Installer] Invisible titlebar (logo/title/close button), blurry UI and misaligned hover targets at 100% display scale

[BambooFury]

Description

On displays with 100% scale (regular Full HD 1920x1080 monitors, not 4K), the installer window (v1.12.1) renders incorrectly:

• The custom titlebar is empty - no Millennium logo, no title text, and the close button is invisible (it still works if you blind-click the top-right corner).
• All text looks slightly blurry, as if the surface is stretched.
• Hover targets are vertically misaligned - e.g. for "change version" you have to hover slightly below the visible text.

On 150% scale everything renders perfectly.

Reproduction

1. Use a regular Full HD (1920x1080) monitor at 100% Windows display scale.
2. Launch the installer → broken titlebar / blurry UI.
3. Switch scale to 150% → works fine.

Environment

• Windows, 2x Full HD (1920x1080) monitors, both at 100% scale (no 4K/HiDPI display involved)

bandicam.2026-07-04.21-14-41-793.mp4

[BambooFury]

A more detailed video

bandicam.2026-07-05.09-22-12-420.mp4

[BambooFury]

Hey @shdwmtr 👋

Found the root cause and opened a fix: #15
The borderless frame is applied while the window is still hidden, so DWM composites it with stale geometry at 100% scale - that's why the titlebar disappears and the UI looks blurry. At 150% it works by accident: GLFW_SCALE_TO_MONITOR triggers a resize that forces DWM to recomposite.
The fix nudges the window rect by 1px and back after showing it. Tested at 100% and 150%, video below.

bandicam.2026-07-05.10-30-11-437.mp4