Stuttery resizing when OpenGLContext is attached

Hi everyone,

I updated my project to the latest develop branch (commit state as of March 3, 2026) and unfortunately I’m seeing very bad stuttering / choppy behaviour when dragging the resizebar, but only when an OpenGLContext is attached.

Without the OpenGLContext everything resizes smoothly .

I’ve attached:

· a short video clearly showing the stuttering .

· a minimal example project (zipped source code) that reproduces the issue .

Thank you all for your help and time!

RsizebarOGLContextBug.zip (5.8 KB)

Additionally, I’d like to mention that in the attached minimal example the issue is somewhat difficult to reproduce consistently. However, in a more complex application with additional controls and a more elaborate UI an update/repaint is sometimes missed: after dragging the resize bar and releasing the mouse button, the view does not refresh. When this happens, the UI fails to update properly and components visually overlap. Only dragging the resize bar again triggers another update/repaint cycle, which then corrects the layout. This issue has never occurred so far in JUCE 8.0.11.

@reuk Additionally, this regression seems to have exactly started with this commit:

Direct2D: Use WM_PAINT and vblank callbacks to drive painting
Commit hash: 258203706cdfc1357effe8cc752672b793cea37d
Commit date: 17.12.2025