This is a fork of Extended Link Properties by Torisugari (now disabled).
Based on version 1.2.5 from forum.addonsmirror.net (saved page on web.archive.org).
Continuation of my old (unofficial) development: forum.mozilla-russia.org/viewtopic.php?pid=376740 (and following).
Source code and issues tracker: https://github.com/Infocatcher/Link_Properties_Plus
[x] Fixed compatibility with Firefox 48+ (due to changes in nsIIOService, see bug 1254752).
[x] Fixed integration with Page Info window in Firefox 44+ (#22).
[+] Added Chinese (Simplified) locale (zh-CN), thanks to YFdyh000 (#23).
[*] Improved startup performance: code around context menu and commands was moved into lazily loaded separate file (#21).
[x] Fixed compatibility with future Firefox versions: don't use Array generics like `Array.forEach()` (bug 1222547).
[+] Show HSTS redirect flag in tooltip for “Direct Link” field.
[*] Updated compatibility with Private Tab extension: track toggling of private state using tab duplication in Firefox 51+ (see Private Tab #244).
[x] Fixed URIs validation in Firefox 37-43 (caused by `nsIIOService.newChannelFromURIWithLoadInfo(…, null)` failure).
[x] Fixed detection of opening file dialog in Firefox 52+.