Repro steps:

1) Open the project
2) Open LoadBundles.cs script and comment line 58 (www.assetBundle.Unload(false))
3) In the menu bar AssetBundles click: Build for WebGL; Use extension .unity3d and Build Asset Bundles
4) Build the LoadBundles scene and move Webgl.unity3d folder from AssetBundles folder to {{build}}/Release/bundles
5) Rebuild and run the project through localhost(by default if you click Build and Run)
6) Open the generated localhost address in Incognito(Private) mode of browser
7) Notice in the task manager that the Memory usage rises drastically sometimes crashing the browser

N.B. Sometimes the bug doesn't reproduce so Rebuilding or reloading the browser helps. Sometimes it reproduces in normal window, but bigger chance in Incognito