It may be injected ads, a virus, or adware. I experienced something a bit similar on Chrome on one of my S4's (injected ads); whenever I opened the browser, I am taken to the Play Store prompting me to install an app. A factory reset + backup removed it.
3 years ago, I also installed a particular room escape game, and when I went to Chrome, a random animation showed up, and it was a virus; I removed the app, and it disappeared. However, I don't know what kinds of damage it has done (fortunately I did that factory reset + backup that I mentioned a while ago after I accidentally triggered the android acore glitch again)
However, I have also occasionally ended up on adware sites for some reason (even on popular websites such as About) and I'm still not exactly sure why this is happening. I tried installing the Anti Adware app, and it detected apps with ad permissions (the "nöid" voice changer app being the only one I remember having when I started ending up in adware sites, so this may be the case)
Based on this, maybe a particular app is causing this (such as that room escape game I had).