diff --git a/internal/graphicsdriver/opengl/context.go b/internal/graphicsdriver/opengl/context.go
index 93707e494..079f659a2 100644
--- a/internal/graphicsdriver/opengl/context.go
+++ b/internal/graphicsdriver/opengl/context.go
@@ -19,6 +19,7 @@ import (
 	"sync"
 
 	"github.com/hajimehoshi/ebiten/v2/internal/graphicsdriver"
+	"github.com/hajimehoshi/ebiten/v2/internal/graphicsdriver/opengl/gl"
 )
 
 type blendFactor int
@@ -87,7 +88,28 @@ func convertBlendOperation(o graphicsdriver.BlendOperation) blendOperation {
 	}
 }
 
+type (
+	textureNative      uint32
+	renderbufferNative uint32
+	framebufferNative  uint32
+	shader             uint32
+	program            uint32
+	buffer             uint32
+)
+
+type (
+	uniformLocation int32
+	attribLocation  int32
+)
+
+const (
+	invalidFramebuffer = (1 << 32) - 1
+	invalidUniform     = -1
+)
+
 type context struct {
+	ctx gl.Context
+
 	locationCache      *locationCache
 	screenFramebuffer  framebufferNative // This might not be the default frame buffer '0' (e.g. iOS).
 	lastFramebuffer    framebufferNative
@@ -100,6 +122,7 @@ type context struct {
 	maxTextureSizeOnce sync.Once
 	highp              bool
 	highpOnce          sync.Once
+	initOnce           sync.Once
 
 	contextImpl
 }
@@ -159,3 +182,31 @@ func (c *context) getMaxTextureSize() int {
 	})
 	return c.maxTextureSize
 }
+
+func (c *context) reset() error {
+	var err1 error
+	c.initOnce.Do(func() {
+		// Load OpenGL functions after WGL is initialized especially for Windows (#2452).
+		if err := c.ctx.LoadFunctions(); err != nil {
+			err1 = err
+			return
+		}
+	})
+	if err1 != nil {
+		return err1
+	}
+
+	c.locationCache = newLocationCache()
+	c.lastTexture = 0
+	c.lastFramebuffer = invalidFramebuffer
+	c.lastViewportWidth = 0
+	c.lastViewportHeight = 0
+	c.lastBlend = graphicsdriver.Blend{}
+
+	c.ctx.Enable(gl.BLEND)
+	c.ctx.Enable(gl.SCISSOR_TEST)
+	c.blend(graphicsdriver.BlendSourceOver)
+	c.screenFramebuffer = framebufferNative(c.ctx.GetInteger(gl.FRAMEBUFFER_BINDING))
+	// TODO: Need to update screenFramebufferWidth/Height?
+	return nil
+}
diff --git a/internal/graphicsdriver/opengl/context_js.go b/internal/graphicsdriver/opengl/context_js.go
index f395720d1..13f68c2d6 100644
--- a/internal/graphicsdriver/opengl/context_js.go
+++ b/internal/graphicsdriver/opengl/context_js.go
@@ -25,48 +25,11 @@ import (
 	"github.com/hajimehoshi/ebiten/v2/internal/shaderir"
 )
 
-type (
-	textureNative      uint32
-	renderbufferNative uint32
-	framebufferNative  uint32
-	shader             uint32
-	program            uint32
-	buffer             uint32
-)
-
-type (
-	uniformLocation int32
-	attribLocation  int32
-)
-
-const (
-	invalidFramebuffer = (1 << 32) - 1
-	invalidUniform     = -1
-)
-
 type contextImpl struct {
-	ctx    gl.Context
 	canvas js.Value
 	webGL2 bool
 }
 
-func (c *context) reset() error {
-	c.locationCache = newLocationCache()
-	c.lastTexture = 0
-	c.lastFramebuffer = invalidFramebuffer
-	c.lastViewportWidth = 0
-	c.lastViewportHeight = 0
-	c.lastBlend = graphicsdriver.Blend{}
-
-	c.ctx.Enable(gl.BLEND)
-	c.ctx.Enable(gl.SCISSOR_TEST)
-	c.blend(graphicsdriver.BlendSourceOver)
-	f := c.ctx.GetInteger(gl.FRAMEBUFFER_BINDING)
-	c.screenFramebuffer = framebufferNative(f)
-
-	return nil
-}
-
 func (c *context) blend(blend graphicsdriver.Blend) {
 	if c.lastBlend == blend {
 		return
diff --git a/internal/graphicsdriver/opengl/context_notjs.go b/internal/graphicsdriver/opengl/context_notjs.go
index cbe3af6ff..ee7b16e5e 100644
--- a/internal/graphicsdriver/opengl/context_notjs.go
+++ b/internal/graphicsdriver/opengl/context_notjs.go
@@ -26,51 +26,7 @@ import (
 	"github.com/hajimehoshi/ebiten/v2/internal/shaderir"
 )
 
-type (
-	textureNative      uint32
-	renderbufferNative uint32
-	framebufferNative  uint32
-	shader             uint32
-	program            uint32
-	buffer             uint32
-)
-
-type (
-	uniformLocation int32
-	attribLocation  int32
-)
-
-const (
-	invalidFramebuffer = (1 << 32) - 1
-	invalidUniform     = -1
-)
-
 type contextImpl struct {
-	ctx  gl.Context
-	init bool
-}
-
-func (c *context) reset() error {
-	if !c.init {
-		// Load OpenGL functions after WGL is initialized especially for Windows (#2452).
-		if err := c.ctx.LoadFunctions(); err != nil {
-			return err
-		}
-		c.init = true
-	}
-
-	c.locationCache = newLocationCache()
-	c.lastTexture = 0
-	c.lastFramebuffer = invalidFramebuffer
-	c.lastViewportWidth = 0
-	c.lastViewportHeight = 0
-	c.lastBlend = graphicsdriver.Blend{}
-	c.ctx.Enable(gl.BLEND)
-	c.ctx.Enable(gl.SCISSOR_TEST)
-	c.blend(graphicsdriver.BlendSourceOver)
-	c.screenFramebuffer = framebufferNative(c.ctx.GetInteger(gl.FRAMEBUFFER_BINDING))
-	// TODO: Need to update screenFramebufferWidth/Height?
-	return nil
 }
 
 func (c *context) blend(blend graphicsdriver.Blend) {