Fix failure to restore compressed textures after WebGL context loss.

changelog/3.90/CHANGELOG-v3.90.md

@@ -6,6 +6,7 @@
 
 # Bug Fixes
 
+* Fix failure to restore compressed textures after WebGL context loss.
 * Fix a single WebGL error, with no visual side-effects, from occurring while calling `Shader.setRenderToTexture()` after the game has started running. Actually, the root cause was leaving new WebGL textures bound after creation.
 
 ## Examples, Documentation, Beta Testing and TypeScript

src/renderer/webgl/WebGLRenderer.js

@@ -818,6 +818,9 @@ var WebGLRenderer = new Class({
             gl.disable(gl.DEPTH_TEST);
             gl.enable(gl.CULL_FACE);
 
+            // Re-enable compressed texture formats.
+            _this.compression = _this.getCompressedTextures();
+
             // Restore wrapped GL objects.
             // Order matters, as some wrappers depend on others.
             var wrapperCreateResource = function (wrapper)