How to reproduce:
1. Open the “SplineYGridIssue“ project
2. In the Project window open the “Assets/_Safeguard/Runtime/Prefabs/Splines [Fast].prefab” Prefab
3. In the Hierarchy window select the “Spline - Turn Right” GameObject
4. Make sure to open the Scene view
5. From the Tools bar select “Tool context” then select “Draw Splines Tool”
6. In the Scene view select any light blue indicator from the “Spline - Turn Right” GameObject
7. In the Scene view overlays disable “Toggle the visibility of the grid”
8. Drag the mouse around in the Scene view and observe it

Expected result: New spline lines are rendered
Actual result: New spline lines are not rendered

Reproduced with: 2.1.0 (2021.3.38f1), 2.6.0 (2022.3.27f1, 6000.0.0f1)

Reproduced on: Windows 11
Not reproduced on: No other environment tested

Notes:
1. Not reproducible when “Toggle the visibility of the grid” is enabled
2. Images of expected and actual results are provided in the internal comments