Use the following recommended Quality settings to optimize your builds for the Unity Web platform.
Configure the following recommended settings in Edit > Project Settings > Quality. For more information on these settings, refer to Quality.
The Quality settings contain a group of possible Quality Levels for your build. If you set your Quality Level to a lower setting (Very Low or Low), it results in faster load times and better performance which is recommended for a Web application. However, lower quality can mean the visuals don’t look as good.
For more information about this setting, refer to Quality.
To change the Quality Level via script instead, add this code to one of your scripts:
QualitySettings.SetQualityLevel(0, true); // Use the index of your quality settings matrix (0 = Very Low, 1 = Low).