I have already reported this issue through Opera's official bug reporting system.
Reference: BS-104581

The issue occurs intermittently when “Responsive” is selected in the DevTools Device Toolbar.

When the issue occurs, reloading the page while “Responsive” mode is active may cause the layout viewport to be initialized incorrectly, even though the Device Toolbar still displays the expected dimensions.

For example, with Responsive mode set to 320 × 568, I observed:

window.innerWidth: 1868
document.documentElement.clientWidth: 1868
window.visualViewport.width: 1868
window.screen.width: 320

As a result, mobile CSS media queries do not match and the page is rendered as tablet/desktop.

Resizing the responsive viewport slightly immediately recalculates the viewport correctly.

The issue does not occur when a specific device preset is selected. Switching from “Responsive” to a phone preset and back to “Responsive” may also temporarily clear the issue.

Steps to reproduce:

1. Open DevTools.
2. Enable Device Toolbar.
3. Select “Responsive”.
4. Set the viewport to 320 × 568.
5. Reload the page.
6. When the issue occurs, the Device Toolbar still shows 320 × 568, but the layout viewport reports a much larger width.
7. Resize the responsive viewport slightly.
8. The viewport is immediately recalculated correctly.

Expected:
The layout viewport should always match the dimensions shown in Responsive mode after reload.

Control test:
Selecting a specific phone preset and reloading initializes the viewport correctly.

The issue is also reproducible with a standalone HTML file without React, Vite, SCSS or any framework.

Environment:
Opera One: 135.0.5973.41
Chromium: 151.0.7922.138
Windows 11 64-bit
Stable channel

Kind Regards

if there only one, the amount of space it leaves gives me bad expirience

ETA: However, volume booster levels set in the horizontal bar appear to "stick" after switching to the vertical bar. So, while you can't use the volume booster control with vertical tabs, you may be able to use the feature if you set a tab's level in the horizontal bar.

The good news is that an awesome Opera dev made a browser.js fix to work around Pluto blocking Opera. It's in the new 135.0.5973.76 build that just came out.

burnout426

Volunteer

last edited by about 6 hours ago

If those extra entries correspond to the inactive search list at the URL opera://settings/searchEngines, then that's bug RNA-3999 that is already fixed in 135.0.5967.0 and newer so far. I don't think the fix has been backported to 134.
There's also another bug with those inactive searches working in the address field. That's RNA-4324 and just got fixed in Opera Developer 136.0.5988.0.

Thanks for the detailed explanation! Hopefully the fixes will be backported to Opera 134 soon for users still affected.

hello,
first of all thank you for your answer which I am trying to put in place, the chrompass software is rejected by my avira security antivirus, and despite the unblocking of security by windows defender...

There have just been opera and windows updates, and opera still had difficulty displaying my Google account password, even though I could clearly see my email address and the associated password on the login page.

I had to go into Opera settings and retrieve my Google account password (copy) to put it on my Google account login form.

My Google identifiers were recorded by Opera, but Opera seemed unable (and after several attempts!) to insert my MDP in the intended location.

I will take my time and try to follow your instructions. Thanks a lot.

For your regular installs, I'd goto the URL opera://settings/content/all, type chatgpt.com in the search field and click "Delete displayed data". Then, repeat for openai.com. Then, goto the URL opera://settings/clearBrowserData and clear "Cached images and files" for all time. Then, log back in to chatgpt.com and see if the issue still happens.

Note also that sometimes force dark mode can get stuck on in some rare cases where the only way to fix it is to goto the URL opera://settings/reset and reset just your settings. You'll usually lose open tabs though. Trying in a test standalone installation will tell you if resetting your settings will even help.

Are all 3 computers on Windows?

Have you messed with the "Forced colors" and "Force color profile" settings at the URL opera://flags?

Is there any difference if you switch to another them and switch back to the Classic theme? Maybe reset the classic themes settings too if you haven't.

Any difference with "graphics acceleration" disable at the URL opera://settings/system?