[WebGL] .data.unityweb is not cached in Desktop Safari

Delivering the compressed version of our **WebGL build** (within Facebook Canvas) to **Safari** ,**Chrome** and **Firefox** with Data Caching checked, that really works in **Chrome** and **Mozilla Firefox** after upgrading to **Unity 2018.3.1f1**.

Found a fix here:
[WEBGL.DATA.UNITYWEB IS NOT CACHED IN THE INDEXED DB](https://issuetracker.unity3d.com/issues/webgl-data-dot-unityweb-is-not-cached-in-the-indexed-db)

However for us it looks like it fails in case of **Safari Browser**.Just looking for a workaround.

We are using Safari version (11.1.2).Unfortunately, it's unable to cache the "**WebGL.data.unityweb**" of size **47.8MB** and the **Asset Bundles**.The large data file is downloading every time.

Does the above fix applicable for **Safari** also ?

What we can see in browser console is:

WebGL.wasm.code.unityweb and WebGL.wasm.framework.unityweb ate cached in browser memory but not WebGL.data.unityweb.

Getting the following errors in console (**Safari Browser**):

1.[UnityCache] indexedDB database could not be opened 2.[UnityCache] WebGL.wasm.framework.unityweb' successfully downloaded but not stored in the indexedDB cache due to the error: Error: indexedDB access denied 3.IndexedDB is not available. Data will not persist in cache and PlayerPrefs will not be saved.

How would we be able to find a way out?