Notes: This happens on 2020.1.0a1 as well as on the latest version of SRP 7.1.1. This bug has existed since version 4.10.0 in 2018.4.4f1
1. What happened
VFX graph particles are not animating correctly. At 60 FPS, there is noticeable flicker, what looks like the flipbook is going backwards through the animation every couple of frames.

2. How we can reproduce it using the example you attached
Repro steps:
1. Open "newscene" scene
2. Observe the bad looking effect animation
3. Open Fire.vfx graph
4. Note how the the animation now runs much smoother
5. Click "Force Runtime Mode"
6. Note how the animation now looks bad again
7. Try running play mode and see how it looks

Expected result: the VFX should look the same regardless of whether the VFX graph editor is open
Actual result: the VFX looks terrible when the VFX graph isn't open and when "Force runtime mode" is enabled

Note: this seems to be specific to 7 by 7 flipbooks. I have tested 5 by 5 flipbooks and it doesn't happen. It doesn't happen with any other dimensions that I've tried either.