A couple of bugfixes have been made for MV 1.3.0. Be sure to get the newest and updated version! And be sure to follow all these steps to update your game:

1. Make a backup of your project.
2. Make a backup of your Generator folder if you edited it. If you already upgraded from 1.2.0 this is unnecessary.
3. If you have an old project that needs updating, Create a new project or go to the NewData folder in your RPG Maker MV root folder. Copy the new js (including libs folder but don’t copy plugins.js) and index.html files to your current project!
4. Replace BGM files if you got it from 1.3.0.

Step 4 is newly added. So be sure to follow that if you haven’t. Here’s a quick list of the changes:

• Fix for a number of glitches in v1.3.0
• Fix for scrolling flicker in WebGL mode
• Fix for the change tileset issue
• Fix for WEBGL: INVALID_VALUE issue
• Fix for the black lines on android
• Fix for the sound not looping (replace in your project from NewData\audio\bgs)
• Fix to NoAutoshadow.js
• Fix enccryption error
• Updated splash screen plugin
• Enabled Pixi4 Garbage Collector
• Fixed ImageManager.clear bug
• Partly fixed fade or screen effects.

For those who would like to know the changes to the core code for RPG Maker MV from 1.3.0 to 1.3.1, look below: 

rpg_core.js

• CacheEntry.free function fixed
• Tilemap’s TileRenderer mode will automatically default to Nearest Neighbor
• ScreenSprite updates
  • New properties added: anchor and blendMode
  • ScreenSprite.initialize
  • ScreenSprite.setColor
• WebAudio.onXhrLoad function fixed

rpg_managers.js

• No changes

rpg_objects.js

• No changes

rpg_scenes.js

• No changes

rpg_sprites.js

• No changes

rpg_windows.js

• No changes

And there you have it! Happy updating!