Android / Network / Cloudflare / Web
Understand the fault before changing things.
Wenvo Lab is a practical technical notebook and a set of browser tools that do not upload your input. It focuses on Android, networks, Cloudflare and web troubleshooting.
Notes · 25
Field notes
Each guide begins with a real symptom, keeps the useful steps, and says when to stop changing things.
My Website Worked on Wi-Fi. Then I Tried Mobile Data.
The same domain can take different paths over Wi-Fi and cellular networks. DNS, IPv4, IPv6, carrier routing, CDNs and caching can make one connection work while another fails.
WebI Added Dark Mode. Somehow I Ended Up With Three Different Dark Modes.
Dark mode looks like a boolean until system preferences, saved choices, initial rendering and browser UI arrive. Reliable theme logic usually needs three states, not two.
WebYour Website Returned 200 OK. Everything Was Absolutely Not OK.
HTTP 200 only means the server successfully returned a response. That response can still be an error page, stale content or the wrong application entirely.
WebBase64 Is Not Magic. It’s Just Your File Wearing a Very Expensive Costume.
Base64 turns binary data into text for APIs and data URLs. The price is larger payloads, extra memory and some terrible ideas involving giant images.
WebCORS: The Browser Knows the API Exists. It Just Won’t Let You Touch It.
Your API works in curl and Postman, but the browser blocks it. CORS is a browser security rule about which origins may read cross-origin responses.
WebIt Works in Chrome. Then Safari Enters the Room.
A feature working in Chrome does not mean it works on the web. Browser engines, permissions, layout rules and mobile behavior can turn a finished feature into a second debugging project.
WebPWA vs normal websites: why some sites can be installed like apps
A PWA is still a web application, but manifests, service workers and browser APIs give it installation, caching and app-like capabilities.
WebWebP, PNG or JPEG: which image format should you actually use?
Photos, screenshots, transparency and web delivery have different needs. Choose the format for the image, not by age or hype.
SecurityHow to spot a phishing link: the domain matters more than a convincing page
A polished page and a valid HTTPS certificate do not prove identity. Learn to inspect the real domain, redirects and high-risk requests.
WebHow short links work: why a tiny code can open a long URL
Short links do not compress a long URL into a few characters. They store a mapping, then redirect visitors to the real destination.
SecurityWhat is actually inside a QR code — and how to scan one more safely
A QR code is encoded data, not a tiny browser. The real security question is what data it contains and what happens after scanning.
WebHow a cross-device clipboard moves text from your phone to your computer
A temporary server, an unguessable token and sensible expiry are enough to make text feel like it jumped between devices.
NetworkWhat “IP purity” really means — and why some addresses trigger verification
“IP purity” is not a universal standard. Reputation, ASN type, shared usage and behavioural signals are what platforms actually evaluate.
WebCookie vs LocalStorage vs SessionStorage: what websites keep in your browser
Three browser storage mechanisms can all remember state, but their lifetime, request behaviour and security properties differ.
SecurityWhat HTTPS actually protects — and what the lock icon does not prove
HTTPS encrypts a connection and authenticates the domain endpoint, but it is not a certificate of good intentions.
WebWhy a website can stay old after it has already been updated
Browser cache, CDN cache and service workers can each keep an older copy alive. Learn how to tell which layer is responsible.
NetworkWhat a DNS lookup actually checks
A practical map of A, AAAA, CNAME, MX, TXT and NS records, plus caching and CDN surprises.
PrivacyHow to remove location data from a photo
A reliable copy, clean, verify workflow—and the difference between hiding a place and changing the file.
PrivacyWhy photos carry EXIF metadata
What the hidden camera notes contain, why they exist, and when GPS data deserves attention.
WebDebugging a mobile web page without guessing
Use Console, Network, Elements and storage inspection to replace “the page is broken” with evidence you can act on.
NetworkWhen IPv6 works halfway: a DNS-first checklist
Having an IPv6 address is only the first layer; test DNS, routing, VPN coverage, MTU and browser fallback separately.
CloudflareA quiet Cloudflare Pages workflow with GitHub
Keep repository state, build output, deployment and DNS as separate layers with an explicit rollback path.
NetworkWhat a WebRTC leak test actually tells you
An IP on a test page is not automatically a proxy leak; candidate type, address scope and a before-and-after comparison matter.
AndroidTermux package errors: a repair order that avoids reinstalling
Classify mirror, signature, dependency, installation-source and storage errors before reaching for a reinstall.
AndroidWhy Shizuku wireless debugging keeps disconnecting
Separate expected reboot behaviour, a lost wireless-debugging session and an app-permission problem before changing anything.
Toolkit · 01—12
Browser tools
Your input stays on this page. There are no accounts, upload queues or cloud history.
JSON Formatter
Format, validate and inspect JSON without uploading it.
02Timestamp Converter
Convert Unix timestamps and readable dates in both directions.
03UUID Generator
Generate cryptographically random UUID v4 values in your browser.
04Base64
Encode or decode UTF-8 text locally.
05URL Encode / Decode
Safely encode query values and decode percent escapes.
06Hash
Calculate SHA-256, SHA-384 or SHA-512 digests locally.
07QR Code
Create a QR code entirely in the browser.
08Browser Info
Read the user-agent and a few browser capability signals.
09Screen Info
Check viewport, screen and pixel density values.
10Text Diff
Compare two text blocks line by line in the browser.
11Markdown Preview
Preview a safe, practical subset of Markdown.
12Color Converter
Convert HEX colors to RGB and HSL.