Opera is good but lack of vertical tabs makes it unusable for work purposes. Now even Brave and Firefox (finally) has it inbuilt (see attachments)
I use my work browser where I have open more than 400 tabs and most of them are in tab groups (subsequent request) that are saved and synced. As of now there are 2000 tabs since Sept 2024.
If Opera wants me to jump from Chrome, understand what you bringing that differentiates you the top competitor. Since Google search, which is your default, forces me to jump back to Chrome on all opera browsers on all devices. And in terms of work, Opera is not upto the standards of 2025 despite redesigning. If I use Google search, it forces me to login then it shows popups to install chrome which is better than Opera (opera ads are wasted if chrome via google is calling us back constantly like poke feature from FB, if you know).
If I remember around 20 years ago, Opera had vertical tabs but don't know what happened, but I believe there is a time for everything as it needs to come to back since browsing is not what was in 2010 in 2025.
https://www.reddit.com/r/operabrowser/comments/1253ttf/vertical_tabs/
I tried one and only addon present on Opera store but it works sometimes, and takes more space of the webpage unlike vertical tabs which reduce the top bars and vertical tabs section is resizable. Plus it is not updated since 2019. Damn 7 years almost.
https://addons.opera.com/en/extensions/details/vertical-tabs/
Addons to have vertical tabs exist on chrome addon store but none work on Opera unfortunately.
https://chromewebstore.google.com/detail/thready-vertical-tabs/aihcofnnndflfjbmlekiegncnahgmaik
Both vertical tabs and tab groups are needed very much.