Steps how to reproduce with unzipped installer of official en-US SeaMonkey 2.53a1 (NT 6.1; WOW64; rv:56.0) Gecko/20100101 Firefox/56.0 Build 20170711003903 (Default Classic Theme) on German WIN7 64bit: 0. Open above mentioned SeaMonkey after having unzipped installer.exe by double click (in WIN Files Explorer) on “seamonkey.dexe” in folder “core” → via 'Tools → Switch Profile' create and open new User Profile 1. Open attached testdocument1.pdf from (WIN Files Explorer) in AR10 2. Click on string “seamonkey blog” with link behind it Expected: <https://unofficialseamonkeynews.wordpress.com/> opens in Browser Actual: <https://www.seamonkey-project.org/start/> (which ist home page for new user profile when opene first time) opens. 4. Open other page or picture like <https://de.wikipedia.org/wiki/Haselmaus#/media/File:Haselmaus.JPG> Drag and Drop that link form Location Bar to “Home” link in Bookmarks Toolbar 5. Click on string “seamonkey blog” with link behind it Expected: <https://unofficialseamonkeynews.wordpress.com/> opens in Browser Actual: dormouse picture opens. a) Was still ok with unzipped installer of official SeaMonkey 2.53a1 (NT 6.1; WOW64; rv:56.0) Gecko/20100101 Firefox/56.0 Build 20170706013410 (Default Classic Theme) on German WIN7 64bit b) Same effect from other documents not opened in SeaMonkey, for example Link in “Help – About” from Filezilla or Audacity 2.0.1
c) no obvious DUP found in <https://bugzilla.mozilla.org/buglist.cgi?cmdtype=dorem&remaction=run&namedcmd=DUPs1380566&sharer_id=41036>
Created attachment 8886032 [details] Document for tests For a test please proceed as per original report.
d) In some cases (may be dependent on Browser and Tabbed Browsing preferences) not the Home Page, but "Untitled" might be opened.
Works for me. This is likely fallout from bug 1379369. The bug affects all urls passed from the outside to SeaMonkey. Let me know if you want a later test build. Still need some time to fix it properly.