Even thought there are default frames, you can create as many custom frames as you want for Tooltip Overhaul.
Below is a step-by-step explanation of how to design them.

You can use any existing modid for your custom frames. Create a texture pack with the modid tooltipoverhaul. Inside it, add the texture files wherever you want, for example: assets/_<modid>_/textures/overlay/....

Let's suppose we dragged a frame overlay inside assets/biomancy/textures/overlay/testing_frame.png in our texture pack. To use it, in your custom_frames.json, just call the texture this way:

"texture": "biomancy:textures/overlay/testing_frame.png"

The base template size is 132x132n, where:

• 132 x 132 is the size of a single frame
• n is the total number of frames stacked vertically (just for animated overlays)

The mod automatically detects the number of frames based on the image height, so you don’t need to set anything manually if you're making an animated overlay.

To design a simple overlay:

• Create an image of 132x132 pixels
• Each square (44x44) in the template corresponds to a specific position along the tooltip’s edges. The central square does nothing.

Example template:

To clarify:

1. The top-left square corresponds to the top-left edge of a tooltip
2. The black line corresponds to the tooltip border
3. Both the black line and the squares at the background are only intended to indicate the parts of the template, so they should be removed

You do not need to design all quadrants, just the ones you want to customize.

• Stack each frame directly below the previous one in a spritesheet
• Keep each frame exactly 132 × 132 pixels
• For instance, a 10-frame animated overlay would need to have this exact dimensions: 132x1320
• The mod will automatically detect the amount of frames