01 / Performance
Lab data and field data: why they’re different
Lab measurements run in a controlled environment with a defined device and network profile. They are useful for reproducing conditions and inspecting technical bottlenecks. Field data is collected from real users and varies with their devices, networks and visit patterns.
When reading a report, check which kind of data a metric represents and what time period it covers. A lab improvement does not automatically prove that real-user experience improved; a field trend may also need time to reflect a release.
A responsible audit should label the source of each measurement and explain what it can—and cannot—tell you.
02 / CSS
A quick checklist for horizontal overflow
Start by reproducing the issue at the affected viewport width. Inspect wide images or tables, fixed-width cards, long strings without break opportunities, transforms, absolutely positioned elements and nested containers that exceed the viewport.
Prefer correcting the element that causes the overflow over adding a global overflow-x: hidden rule. Hiding overflow can conceal content and make a layout problem harder to discover.
After a change, review the page at nearby viewport sizes and check keyboard focus, sticky elements and any content near the edge of the screen.
03 / Repair safety
Preview a website change before it goes live
Record the original state and the exact symptom. Make one narrow change at a time, preview it in a staging environment or isolated browser session, and compare relevant pages and screen sizes.
Before production changes, confirm that a backup and rollback path exist. Ask who approves the change, what success looks like, and how the issue will be verified afterward. If the evidence is uncertain, stop and investigate rather than claiming a fix.
FIXEEM is being designed around this principle: detect, diagnose, propose, preview, approve, apply and verify.