sdl2-compat: Don't suppress the initial size event for fullscreen windows

SDL Commits
1 
From bd7395f5b77f02e8a50552a4021527aee5210afd Mon Sep 17 00:00:00 2001
From: Frank Praznik <[EMAIL REDACTED]>
Date: Sun, 15 Mar 2026 16:32:37 -0400
Subject: [PATCH] Don't suppress the initial size event for fullscreen windows

Otherwise, the fullscreen size won't be delivered if the window enters fullscreen immediately.

Checked to not regress the ffplay case mentioned in the comment.
---
 src/sdl2_compat.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/sdl2_compat.c b/src/sdl2_compat.c
index c480c87c..61230791 100644
--- a/src/sdl2_compat.c
+++ b/src/sdl2_compat.c
@@ -2949,9 +2949,9 @@ EventFilter3to2(void *userdata, SDL_Event *event3)
                             SDL3_SetNumberProperty(props, PROP_WINDOW_EXPECTED_WIDTH, event2.window.data1);
                             SDL3_SetNumberProperty(props, PROP_WINDOW_EXPECTED_HEIGHT, event2.window.data2);
                             SDL3_SetFloatProperty(props, PROP_WINDOW_EXPECTED_SCALE, SDL3_GetWindowDisplayScale(window));
-                            if (!expected_w || !expected_h) {
-                                /* Don't send the initial size, SDL2 didn't in this case.
-                                 * ffplay breaks if the initial size is sent, see https://github.com/libsdl-org/sdl2-compat/issues/268 for details.
+                            if (!(SDL_GetWindowFlags(window) & SDL2_WINDOW_FULLSCREEN) && (!expected_w || !expected_h)) {
+                                /* Don't send the initial windowed size, SDL2 didn't in this case.
+                                 * ffplay breaks if the initial windowed size is sent, see https://github.com/libsdl-org/sdl2-compat/issues/268 for details.
                                  */
                                 break;
                             }