What are the open source and free web apps for motion graphics design that offer 4k export and no watermark?

There are several open-source and free web applications for motion graphics design that may offer features including 4K export without watermarks. Here are a few notable options:

1. **Blender**:
   - **Description**: Primarily known as a 3D modeling and animation tool, Blender also has robust video editing capabilities and animation features that can be used for motion graphics.
   - **4K Export**: Supports 4K export without watermarks.
   - **Platform**: Desktop application (Linux, macOS, Windows).

2. **Natron**:
   - **Description**: An open-source compositing software that is similar to Adobe After Effects. It is powerful for visual effects and motion graphics.
   - **4K Export**: Supports high-resolution output including 4K.
   - **Platform**: Desktop application (Linux, macOS, Windows).

3. **OpenShot**:
   - **Description**: While primarily a video editor, OpenShot has motion graphics capabilities such as keyframe animations, which can be useful for simple motion graphics projects.
   - **4K Export**: Supports 4K and does not impose watermarks.
   - **Platform**: Desktop application (Linux, macOS, Windows).

4. **Shotcut**:
   - **Description**: Another open-source video editor that includes features for motion graphics, like filters and effects that can be animated.
   - **4K Export**: Offers 4K support and no watermarks.
   - **Platform**: Desktop application (Linux, macOS, Windows).

5. **DaVinci Resolve (Free Version)**:
   - **Description**: Primarily a color grading, video editing, and visual effects software, DaVinci Resolve offers advanced motion graphics capabilities with its Fusion module.
   - **4K Export**: The free version supports 4K resolutions, though some features are limited compared to the paid version.
   - **Platform**: Desktop application (Windows, macOS, Linux).

6. **Kdenlive**:
   - **Description**: A non-linear video editor that allows for some motion graphics capabilities through effects and keyframes.
   - **4K Export**: Supports 4K export and does not impose watermarks.
   - **Platform**: Desktop application (Linux, Windows).

While these are primarily desktop applications, some web-based tools exist, though they might not be fully open-source or may have limitations regarding export formats. Always check the latest features on the respective websites or repositories, as capabilities can evolve.