DEV Community: SoulkiEng

How We Built a 100% Client-Side C2PA Metadata Scrubber, Invisible Unicode Cleaner & NotebookLM Bundler in the Browser

SoulkiEng — Mon, 19 Oct 2026 19:02:54 +0000

As AI workflows matured in 2026, three technical bottlenecks hit developers, creators, and enterprise teams simultaneously:

Binary C2PA & JUMBF Provenance Flags: Even minor edits using Photoshop Generative Fill or Lightroom AI Denoise embed a cryptographic urn:c2pa JUMBF box and IPTC trainedAlgorithmicMedia tag—causing LinkedIn, Instagram, and TikTok to slap an automatic "Made with AI" badge on brand assets.
Hidden Zero-Width Unicode Characters (U+200B, U+202F): Copying text from LLM chat interfaces injects narrow no-break spaces and zero-width joiners that break legacy ATS parsers (like Workday and Greenhouse).
The 50-Source Limit in Google NotebookLM & 20-File Cap in Claude: Even though a single NotebookLM source accepts up to 500,000 words, uploading 50 short 3-page PDFs or Markdown files exhausts all 50 slots immediately.

To solve all three without ever uploading private files or confidential prompts to a cloud server, we built AIScrubbers.com — a 100% client-side browser utility suite.

1. Parsing JPEG `APP11` JUMBF & PNG `tEXt`/`iTXt`/`caBX` Chunks in Pure JS

In PNG files, Stable Diffusion, ComfyUI, and Midjourney store entire prompt graphs inside uncompressed tEXt and iTXt chunks, while C2PA manifests reside inside caBX or jumb containers.

Our C2PA & AI Provenance Inspector reads the file's ArrayBuffer locally in browser RAM, parses chunk headers, and flags any C2PA or generator signatures. Then, our C2PA Metadata Remover reconstructs a clean pixel buffer via HTML5 Canvas—and for print creators on Amazon KDP or Etsy, our 300 DPI Print Normalizer injects an IEEE 802.3 CRC32-verified pHYs chunk (11811 pixels/meter = 300 DPI).

2. Bypassing Google NotebookLM's 50-Source Cap with XML Context Bundling

Anthropic's prompt engineering guide recommends wrapping multi-document context in structured <documents> and <document index="n"><source>filename</source> tags.

Using our NotebookLM & Claude 100+ File Merger, you can drop 100+ PDFs, .docx files, CSVs, and code files into your browser and compile a single indexed Master Markdown or PDF file—turning 100 files into 1 source slot while keeping pinpoint source citations intact.

3. Reversible Client-Side PII Redaction & `llms.txt` Generation

Prompt Privacy Scrubber (PII Redactor): Tokenizes emails, SSNs, phones, and API keys ([EMAIL_1], [API_KEY_1]) locally in browser RAM before you paste into ChatGPT, and restores the real values into the AI's reply in 1 click.
ChatGPT Invisible Watermark Cleaner: Strips U+200B, U+202F, U+FEFF, and curly quotes.
Official llms.txt Generator & AI Crawler robots.txt Configurator: Allow OAI-SearchBot and PerplexityBot for AI search citations while blocking training scrapers.

Try the full 16-tool suite free (zero signups, zero server uploads) at https://aiscrubbers.com or view our documentation at GitHub.

How to Fix "File Size Exceeds 2MB / 4MB Limit" on US Visa (CEAC), Canada IRCC & UK VFS Global Portals

SoulkiEng — Mon, 19 Oct 2026 15:53:17 +0000

Every day, thousands of applicants submitting documents to the U.S. Visa CEAC Portal, Immigration, Refugees and Citizenship Canada (IRCC), UKVI (VFS Global / TLScontact), and Mortgage Underwriting Portals hit a wall with strict file-size rejection errors:

US Visa (DS-160 / DS-260 / CEAC / USCIS): "The file size must be 2MB (2,048 KB) or less."
Canada Express Entry & Study Permit (IRCC): "Maximum file size is 4MB per single upload slot."
UK Visa (VFS Global / TLScontact): "File exceeds 5MB limit" or "Password-protected PDFs are not permitted."
Strict University & Civil Service Portals: "Maximum document size: 200KB or 300KB."

Even worse: most applicants try to fix this by uploading their unredacted passports, Social Security Numbers (SSNs), IRS Forms 1040/W-2, and 6-month bank statements to random cloud PDF servers—exposing their most sensitive identity records to third-party storage buckets.

Why Client-Side WebAssembly (Wasm) Is the Safe Solution

With PDFArenaArc, document compression, merging, unlocking, and redaction run 100% locally inside your browser's WebAssembly memory. Zero bytes are ever uploaded to a remote server.

You can also launch the suite with 1 click from your browser toolbar using the Official PDFArenaArc Chrome Extension (Zero Permissions).

1. Fixing the US Visa CEAC & USCIS 2MB Limit

Scanned civil documents, I-864 Affidavits of Support, and multi-page IRS tax transcripts easily reach 10MB–25MB when scanned at 300–600 DPI.

Direct Local Tool: Compress PDF for US Visa (<2MB CEAC Tool)
How it works: Downsamples bloated scanner background layers to crisp 150 DPI while keeping vector text, stamps, and barcodes 100% sharp for consular officers.

2. Fixing the Canada IRCC 4MB "Single-Slot" Rule

IRCC only gives you one upload slot per category (such as Proof of Means of Financial Support or Client Information), requiring you to combine your Letter of Explanation, pay stubs, employment letters, and 6 months of bank statements into one file under 4MB.

Step 1: Combine all files in chronological order using Merge PDF.
Step 2: Shrink the merged packet under 4MB using Compress PDF for Canada PR (IRCC 4MB Tool).

3. Fixing UK Visa (VFS Global & TLScontact) Upload Errors

VFS Global and TLScontact reject encrypted e-statements and oversized tenancy/financial packets.

Remove e-Statement Passwords Locally: Unlock PDF
Shrink Packets Under 5MB: Compress PDF for UK Visa
Convert Color Scans to Black & White (UKVI Recommended): Grayscale PDF

4. Combining Monthly Bank Statements & Tax Forms (Mortgage & CPA Portals)

Mortgage underwriters require consecutive monthly bank statements with all pagination intact:

Mortgage Packet Builder: Merge Bank Statements for Mortgage
IRS / CPA Tax Packet Builder: Merge PDF for Tax Filing
Strict 200KB & 300KB Portal Compressors: Compress PDF to 200KB and Compress PDF to 300KB
Permanent Local Redaction: Redact PDF

Open-Source Documentation & Ecosystem

Web Application: https://pdfarenaarc.com
Official Chrome Web Store Extension: Add PDFArenaArc to Chrome (Free)
GitHub Documentation & Portal Guides: github.com/SoulkiEng/pdfarenaarc
Hacker News Creator Profile: news.ycombinator.com/user?id=cypherrsolution

How to Compress & Merge PDFs for Visa, Tax & Mortgage Portals Without Uploading to Cloud Servers (100% Offline WebAssembly)

SoulkiEng — Fri, 16 Oct 2026 18:35:36 +0000

Every year, millions of applicants uploading sensitive documents to government and financial portals make a dangerous mistake: they upload unredacted passports, SSNs, tax returns, and bank statements to "free" cloud-based PDF compressors.

When you use traditional online PDF tools, your file is uploaded to a remote server, processed in the cloud, and temporarily stored. For a casual flyer, that doesn't matter. For an immigration packet or mortgage underwriting file, it is a massive privacy risk.

Here is how modern Client-Side WebAssembly (Wasm) solves this problem completely inside your browser—with zero server uploads—along with exact specifications for the strictest portals in 2026.

1. US Visa (CEAC / DS-160 / USCIS) — Strict 2MB Limit

The U.S. Department of State CEAC portal strictly rejects any PDF over 2MB (2,048 KB). High-resolution color scans of civil documents or I-864 tax transcripts easily cross 10MB.

Recommended Settings: 150 DPI resolution, Grayscale for text documents.
100% Client-Side Tool: Compress PDF for US Visa (Under 2MB)

2. Canada Express Entry & Study Permit (IRCC) — Strict 4MB Single-Slot Rule

Immigration, Refugees and Citizenship Canada (IRCC) only provides one upload slot per document category and caps each file at 4MB. Applicants must merge multi-year reference letters, paystubs, and T4s into a single file without exceeding 4MB.

100% Client-Side Tool: Compress & Merge PDF for Canada PR (Under 4MB)

3. UK Visa (UKVI / VFS Global / TLScontact) — 5MB Portal Limit

VFS Global document upload portals frequently time out when uploading multi-page tenancy agreements or 6-month bank statements over 5MB.

100% Client-Side Tool: Compress PDF for UK Visa (Under 5MB)

4. Mortgage Underwriting & IRS Tax Filing — Chronological Merging

Mortgage underwriters and CPAs require consecutive monthly bank statements, W-2s, and 1099s combined into a single audit-ready packet without altering original banking encryption or uploading account numbers to third-party servers.

For Home Buyers: Merge Bank Statements for Mortgage Underwriting
For Tax Season: Merge PDF for IRS Tax Filing

5. University & Civil Service Portals — Strict 200KB to 300KB Caps

Many university admission boards and job portals enforce ultra-tight caps between 200KB and 300KB.

200KB Target: Compress PDF to 200KB
300KB Target: Compress PDF to 300KB

Why Client-Side WebAssembly + Zero-Permission Chrome Extension?

We built PDFArenaArc so that every PDF operation—merging, splitting, compressing, redacting, and signing—executes 100% locally in your browser's RAM. You can literally turn off your Wi-Fi after loading the page, and the tools still work at full speed.

For daily workflows, we also published the official PDFArenaArc Chrome Extension on the Google Chrome Web Store with 0 permissions (it cannot read your browsing history or website data).

Try the full private suite for free at https://pdfarenaarc.com.