Bug: Cannot read property 'getExtension' of undefined

[LiFengONE]

Current Behavior

I get this error when useing "pixi.js-legacy": "7.3.3".
TypeError Cannot read property 'getExtension' of undefined
error stack:

let storedGl: WebGLRenderingContext;
let extensions: Partial<CompressedTextureExtensions>;

function getCompressedTextureExtensions()
{
    extensions = {
        s3tc: storedGl.getExtension('WEBGL_compressed_texture_s3tc'),
        s3tc_sRGB: storedGl.getExtension('WEBGL_compressed_texture_s3tc_srgb'), /* eslint-disable-line camelcase */
        etc: storedGl.getExtension('WEBGL_compressed_texture_etc'),
        etc1: storedGl.getExtension('WEBGL_compressed_texture_etc1'),
        pvrtc: storedGl.getExtension('WEBGL_compressed_texture_pvrtc')
            || storedGl.getExtension('WEBKIT_WEBGL_compressed_texture_pvrtc'),
        atc: storedGl.getExtension('WEBGL_compressed_texture_atc'),

bug in detectCompressedTextures
function detection.test return false, but storedGl still is undefined, run detection.remove get this error.

for (const detection of options.detections)
        {
            if (options.skipDetections || await detection.test())
            {
                formats = await detection.add(formats);
            }
            else if (!options.skipDetections)
            {
                formats = await detection.remove(formats);
            }
        }

Expected Behavior

How can I fix this issue with current pixi version, or change another v7 version?

Steps to Reproduce

For low version Android device (version <= 6.0), we use forceCanvas to fallback canvas render, like this.

this.app = new PIXI.Application({
      backgroundAlpha: 0,
      width: this.width,
      height: this.height,
      autoDensity: true,
      forceCanvas: shouldFallbackCanvas
});

Environment

• pixi.js-legacy version: v7.3.3
• Browser & Version: most of Android 5.1
• OS & Version: any

Possible Solution

No response

Additional Information

No response