调用wx.createOffscreenCanvas()，在开发工具中编译通过，且能正常运行，但是在真机调试时总是报错，错误信息如下： [publib]:1 appServiceSDKScriptError Pr.default.OffscreenCanvas is not a constructor; at wx.createOffscreenCanvas TypeError: Pr.default.OffscreenCanvas is not a constructor     at [publib]:1:427374     at Object.eo ([publib]:1:427410)     at Object.<anonymous> ([publib]:1:247770)     at Function.<anonymous> ([publib]:1:799299)     at Object.<anonymous> ([publib]:1:234003)     at test1 (weapp:///pages/heatmap/index.js:115:23)     at H.onReady (weapp:///pages/heatmap/index.js:40:17)     at H.<anonymous> ([publib]:1:1030813)     at H.p.__callPageLifeTime__ ([publib]:1:1030572)     at [publib]:1:1050566