I’m having the same issues. Some thoughts and things I’ve tried:
— It doesn’t appear to be stretching the icons, per se. The icons are showing up huge behind the bubbles, which then stretch to fit the height of those big icons.
— I have virtually no WP Rocket settings enabled.
— I cleared the WP Rocket cache repeatedly.
— There are no server-level or other caches.
— I disabled Photon, as sometimes that can mess with it.
— I resaved the widget settings, in case that would force something good.
— I installed the SVG Support plugin.
— It’s a clean theme (Genesis) with only a dozen plugins; all are well-known, solid, seemingly unrelated plugins.
After all of that, it’s still not working right. I’m out of ideas. We have this on ~20 sites; half work great, and the other half are having this trouble.