SVG Animations pattern edge - svg

Question

I want to create stripe animated background but for some reason can't remove vertical lines that appear on the edge of patterns.
Here is my svg:
<svg width="500" height="500">
<defs>
<linearGradient id='stripe-gradient' x1='0%' y1='0%' x2='100%' y2='100%'>
<stop offset='0%' stop-color='#AAA'></stop>
<stop offset='24.9%' stop-color='#AAA'></stop>
<stop offset='25%' stop-color='#666'></stop>
<stop offset='49.9%' stop-color='#666'></stop>
<stop offset='50%' stop-color='#AAA'></stop>
<stop offset='74.9%' stop-color='#AAA'></stop>
<stop offset='75%' stop-color='#666'></stop>
<stop offset='99.9%' stop-color='#666'></stop>
<stop offset='100%' stop-color='#AAA'></stop>
</linearGradient>
<pattern id='stripe-pattern' width='20' height='20' patternUnits='userSpaceOnUse' >
<rect x='-20' y='0' width='20' height='20' fill='url(#stripe-gradient)' stroke-width='0' stroke='none'>
<animate attributeName='x' from='-20' to='0' dur='0.5s' repeatCount='indefinite'></animate>
</rect>
<rect x='0' y='0' width='20' height='20' fill='url(#stripe-gradient)' stroke-width='0' stroke='none'>
<animate attributeName='x' from='0' to='20' dur='0.5s' repeatCount='indefinite'></animate>
</rect>
</pattern>
<mask id='stripe-mask'>
<rect x='0' y='0' width='100%' height='100%' fill='url(#stripe-pattern)' ></rect>
</mask>
</defs>
<rect class="hbar thing" x="0" y="0" width="200" fill="green" height="200" mask="url(#stripe-mask)"></rect>
</svg>

Answer 1

I know this post is a bit old but in case you still need to solve this issue I have made it work by doubling the stripes, removing one of the rects inside the pattern and then doubling the size of the last rect, c.f., the following code:
<svg width="500" height="500">
<defs>
<linearGradient id='stripe-gradient' x1='0%' y1='0%' x2='100%' y2='100%'>
<stop offset='0%' stop-color='#AAA'></stop>
<stop offset='12.45%' stop-color='#AAA'></stop>
<stop offset='12.5%' stop-color='#666'></stop>
<stop offset='24.45%' stop-color='#666'></stop>
<stop offset='25.5%' stop-color='#AAA'></stop>
<stop offset='37.45%' stop-color='#AAA'></stop>
<stop offset='37.5%' stop-color='#666'></stop>
<stop offset='49.9%' stop-color='#666'></stop>
<stop offset='50%' stop-color='#AAA'></stop>
<stop offset='62.45%' stop-color='#AAA'></stop>
<stop offset='62.5%' stop-color='#666'></stop>
<stop offset='74.95%' stop-color='#666'></stop>
<stop offset='75%' stop-color='#AAA'></stop>
<stop offset='87.45%' stop-color='#AAA'></stop>
<stop offset='87.5%' stop-color='#666'></stop>
<stop offset='100%' stop-color='#666'></stop>
</linearGradient>
<pattern id='stripe-pattern' width='20' height='20' patternUnits='userSpaceOnUse' >
<rect x='-20' y='0' width='40' height='40' fill='url(#stripe-gradient)' stroke-width='0' stroke='none'>
<animate attributeName='x' from='-20' to='0' dur='0.5s' repeatCount='indefinite'></animate>
</rect>
</pattern>
<mask id='stripe-mask'>
<rect x='0' y='0' width='100%' height='100%' fill='url(#stripe-pattern)'></rect>
</mask>
</defs>
<rect x="0" y="0" width="200" fill="green" height="200" mask="url(#stripe-mask)"></rect>
</svg>
I think the vertical stripes appeared as a result of some small numerical issues whenever the browser calculates the position of the two rects. Therefore, the solution is to use only one rect.