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Preview of Block Unreachable Scripts

Block Unreachable Scripts by em_te

Prevent unreachable servers from stalling websites by disabling their scripts if they previously could not load.

3 (7 reviews)3 (7 reviews)
1 User1 User
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Extension Metadata

Screenshots
Popup menu showing which JavaScript requests were unreachable.
About this extension
Some websites load JavaScript from third-party servers that are sometimes unreachable (because of company firewalls/outdated DNS servers/bad SSLs/etc.). This will cause the website to stall (freeze) as it waits for that server to respond. The only recourse is to wait patiently for that request to time out, before the website can continue loading.

This extension will monitor those failed JavaScript requests and will skip over them if any websites try to load from those servers again. This prevents the website from stalling again. The block will only occur for 5 minutes (configurable) in case the server is restored later.

Failed requests can be viewed in the toolbar button, which shows which URLs were blocked and how long the block will last. The toolbar button only appears when scripts are blocked.

Note that this extension does not target anyone and has no black-list or white-list. Blocking only occurs if the server was previously unreachable and therefore the content would not have loaded anyway.

Test the effects of unreachable servers here: http://tinyurl.com/test-blocking-js

This extension will also redirect webpages (not inside iframes) that are unreachable and have a secondary URL hidden within it's primary URL.
Developer comments
How it works:

This extension listens for network connection errors and only watches for script files only. (Network connection errors include connection timeouts, DNS cannot be resolved, etc. and don't include server reported errors like 404 or 500.) When an error occurs, the domain name of the request is put in a List with the time that the error occurred.

This extension also listens for network requests and only watches for script files only. If a request has a domain that matches a domain in the List, the connection is aborted.

A timer checks the List occasionally and removes domains that are older than 5 minutes.
Rated 3 by 7 reviewers
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Permissions and dataLearn more

Required permissions:

  • Access browser tabs
  • Access your data for all websites
More information
Add-on Links
  • Support site
Version
0.5resigned1
Size
16.3 KB
Last updated
a year ago (Apr 25, 2024)
Related Categories
  • Other
License
GNU General Public License v3.0 only
Version History
  • See all versions
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