I have listened to the suggestions of leocg & joshl and have revised my original posting but I seem to have lost the ability to edit my own posts so I'm posting it as a comment instead.
Description: Opera lags when hovering mouse over advertisements and links with long URL's.
Windows 10; Opera Stable 38.0. I've also tried Opera Beta and Developer 39.0, issue persists. Issue is also reproducible in Ubuntu 16.04; Opera 38.0
Issue persists after a clean install & clean new profile.
Steps to reproduce:
Disable ad blockers, including the one built into Opera.
Visit https://youtu.be/t4gjl-uwUHc and watch the video for several seconds, playback should be smooth and fluid, now hover mouse over the advertisement to the right of the video and the video will stutter for a second but then play normally; now rapidly move mouse off and on the advertisement and video will stutter excessively. This video is only one example, you can reproduce this with practically any YouTube video that displays advertisements.
Expected result? Video should continue to play smoothy.
Here's a video of me reproducing the problem, the first three browsers are Google Chrome, Firefox and Microsoft Edge which work as expected; forth browser is Opera which experiences the issue. https://youtu.be/Dr6KpabEfTM
Here's a news article that displays some ads. https://www.theguardian.com/football/blog/2016/jun/12/england-russia-fan-violence-marseille-planning
Keep your mouse off the advertisements and scrolling should be smooth and fluid, now as you scroll make sure you mouse over the ads, scrolling will become jerky and stutter.
Expected result? Scrolling should be smooth when hovering mouse over ads.
My video reproducing the issue, I conduct the same test as before with the same four browsers. It's most noticeable in my first example with the video stuttering but it's still noticeable in this example nonetheless. https://youtu.be/AR5HV-Jbw9g
Same issue happens on another video sharing website. Go to https://vimeo.com/1084537 and scroll down a little until you see the advertisement on the right; now watch the video for a couple seconds and it should playback smoothly, then start rapidly moving your mouse on and off the advertisement and the video will begin to stutter.
Video of me reproducing the issue; video plays smoothy in first three browsers as I rapidly move mouse off and on the advertisement but Opera can't seem to handle the heat. https://youtu.be/47HCfP1OiQQ
This doesn’t happen only on these specific websites, it happens on almost any website when hovering over an ad or link with a super long URL. I understand that I can block ads, but I've made a conscious decision not to and the fact that this doesn’t happen in other browsers means it's a problem with Opera, not the ads. Also, NOT ALL ads cause this issue but it seems like most do.
Link to a picture of the URL that pops up at the bottom of Opera when I hover over that Audible ad seen in my first video.
And this is the full URL of that advertisement…
The intention of this post is not to promote Audible or any other advertisers shown in any way, I simply needed an example of ads that were causing trouble and these were it it.