Go to https://addons.mozilla.org/en-US/firefox/addon/safehistory/ .
To make the addon compatible with recent versions of firefox , rightclick the Add to Firefox button and Save Link As...
Rename it to .zip and open the zip-File ( I used File Roller ). Delete the folder META-INF and open the file install.rdf with a text editor. Change the line 2.0.0.* to 3.6.*
Save the file and put it in the .zip archive. Rename the .zip file to .xpi again.
In Iceweasel or Firefox go to File > Open File.. and browse to the changed safehistory-0.8-fx.xpi
Install the addon and you are done.