Error map
VersionError Console: VersionError: The requested version (1) is less than the existing version (2) — IndexedDB open() failed
Browser · layer 1, On your device
Centre: this error. First ring: errors it is linked with (7). Outer ring: what those are linked with. Colours show the layer of a request each error belongs to. Click any dot to re-centre the map on it; hover to follow its connections. The centre dot opens the error page.
Directly related (7)
QuotaExceededError: Failed to execute 'setItem' on 'Storage': Setting the value exceeded the quota
localStorage/sessionStorage is full (about 5 MB per origin) or storage is disabled.
Chrome: Aw, Snap! Something went wrong while displaying this webpage. Error code: STATUS_ACCESS_VIOLATION / SIGILL / Out of Memory
A Chrome tab crashed — out of memory, a faulty extension, a graphics/driver issue or a very heavy page.
Browser: This network requires you to sign in — captive portal (hotel, airport, café Wi-Fi) blocking HTTPS sites
The Wi-Fi needs a login or acceptance page first; until you complete it, secure sites fail with certificate or connection errors.
Console: Failed to register a ServiceWorker: A bad HTTP response code (404) was received when fetching the script
The browser could not fetch, parse or install the service worker script, or the page is not allowed to register one (HTTPS and sc…
Console: SecurityError: Failed to read the 'localStorage' property from 'Window': Access is denied for this document
The page cannot use `localStorage` because cookies/site data are blocked, it runs in a sandboxed iframe, or the browser is in a r…
Console: Unchecked runtime.lastError: The message port closed before a response was received (extension message)
A browser extension sent or received a message and the other side closed the channel without replying — almost always an extensio…
Console: SecurityError: Failed to execute 'toDataURL' / 'getImageData' on 'HTMLCanvasElement': Tainted canvases may not be exported
You drew an image from another origin onto a canvas without CORS permission, so the browser blocks reading pixels back out.
Two steps away (21)
Azure Storage: AuthorizationPermissionMismatch (403) — This request is not authorized to perform this operation using this permission
You’re accessing blob/queue data with Microsoft Entra ID, but the identity has only management roles (Owner/Contributor) — not a…
net::ERR_BLOCKED_BY_CLIENT
A browser extension (ad blocker, privacy tool) blocked the request.
net::ERR_CONNECTION_REFUSED (This site can't be reached — refused to connect)
The browser reached the host but nothing was listening on that port.
Blue Screen: MEMORY_MANAGEMENT (Stop code 0x0000001A)
Windows detected a severe memory-management error — commonly faulty RAM, unstable memory settings or a bad driver.
RangeError: Invalid array length
An array was created or resized with a negative, fractional or enormous length.
Chrome: This page isn’t working — sent an invalid response. ERR_CONTENT_DECODING_FAILED
The response claims to be compressed (gzip/brotli) but cannot be decompressed — it was double-compressed, truncated or not compre…
HTTP 407 Proxy Authentication Required
A proxy between you and the server requires credentials before it will forward your request.
HTTP 408 Request Timeout
The server closed the connection because the client took too long to send the complete request.
TypeError: Failed to fetch / NetworkError when attempting to fetch resource
The browser couldn’t complete the request at the network level — CORS, DNS, offline, blocked mixed content, or the server refused…
HTTP 404 Not Found
The server can’t find anything at the requested URL.
Refused to execute script from 'x' because its MIME type ('text/html') is not executable
The browser fetched a script but the server labelled it text/html (usually an error page), so it refused to run it.
Failed to load module script: Expected a JavaScript module script but the server responded with a MIME type of "text/html"
A or dynamic import got HTML back instead of JavaScript.
HTTP 431 Request Header Fields Too Large
The request headers — almost always cookies — exceed the server’s size limit.
SecurityError: Blocked a frame with origin "x" from accessing a cross-origin frame.
Script tried to read or modify an iframe (or window) from another origin.
This Set-Cookie was blocked because it had the "SameSite=Lax" attribute but came from a cross-site response / SameSite=None requires Secure
The browser refused to store or send an auth/session cookie because of SameSite or Secure rules — so logins don’t “stick” across…
Chrome: Page Unresponsive — The following page(s) have become unresponsive. You can wait for them to become responsive or exit the page(s)
A tab is stuck in a busy loop or waiting on something heavy, so Chrome offers to wait or kill it.
Console: Uncaught (in promise) Error / TypeError / DOMException — unhandled promise rejection
A promise was rejected and no `.catch()` or `try/catch` handled it, so the browser logs it as an unhandled rejection.
Console: NotFoundError: Requested device not found (getUserMedia has no camera or microphone)
`getUserMedia` found no camera or microphone matching the constraints — the device is missing, disabled or the constraints are to…
CORS Error: No 'Access-Control-Allow-Origin' header is present
The browser blocked a cross-origin request because the server’s response didn’t include the CORS headers allowing your site’s ori…
NotAllowedError: Failed to execute 'writeText' on 'Clipboard': Document is not focused.
The Clipboard API refused to write — the page isn’t focused, there was no user gesture, or the context isn’t secure.
Chrome DevTools: net::ERR_FAILED — a request failed with no specific reason (CORS, extension, mixed content or network)
ERR_FAILED is Chrome’s catch-all for a failed request. In DevTools it very often hides a CORS rejection, an extension, or a block…
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