Google lighthouse error NO <meta name="viewport"> tag found

Technical Q&A

Topic summary

Google Lighthouse (web audit tool) now reports “NO tag found,” causing an SEO score drop from 99 to 77 after further store optimizations.

The meta viewport tag (controls mobile scaling/responsiveness and affects SEO) is shown in the site’s code, but Lighthouse still flags it as missing.

Reverting to the old theme/code does not resolve the error; the issue persists regardless of theme changes.

Evidence is provided via screenshots: previous performance metrics, the current Lighthouse error, and a code snippet showing the viewport tag. The store URL (www.uwdiervoeding.nl) is shared for review.

Status: No fix identified yet. The user requests help to understand why Lighthouse cannot detect the viewport tag despite its presence. The discussion remains open with unanswered questions about the root cause and resolution.

Summarized with AI on January 31. AI used: gpt-5.
1

Hello,

I have a problem with my store, I optimized my store and had a great google lighthouse score of 99 on SEO.

Since I have further optimized my store is gave me a score of 77 on SEO while I did not change anything.

Here are my old performance metrix’s.

Old Performance metrixs
Old Performance metrixs1266×728 47.4 KB

When I change my theme to my old code I still get the error (NO tag found) in the google lighthouse performance report.

New Lighthouse scores with Viewport problem
New Lighthouse scores with Viewport problem1287×718 47.5 KB

Here is the problem:

Meta name problem
Meta name problem1211×225 20.7 KB

In my code i have the meta name viewport included.

Code from my website
Here is the code from my website, can anybody help me with this problem because I do not know what to do.
My store is: www.uwdiervoeding.nl
Regards
Stan Legebeke