Reproduction steps:
1. Open the attached “repro-project“
2. Navigate to the Hierarchy window, right-click, and select Effects → Trail to add a Trail effect
3. Select the newly created GameObject
4. In the Inspector window, locate the “Color” field under the “Trail Renderer” component and click on it to open the Gradient Editor
5. Within the Gradient Editor, click on the color field again to bring up the color wheel
6. Change the colors by clicking on the wheel and moving the cursor around within the color wheel

Expected result: Memory usage remains consistent
Actual result: Memory usage rapidly rises

Reproducible with: 2021.3.37f1, 2022.3.26f1, 2023.2.19f1, 6000.0.0b16

Reproduced on: Windows 10
Not reproducible on: macOS Sonoma 14.4.1 (Intel)

Note: Not reproducible in a newly created project