Release notes for Recoll 1.18.x

Caveats

Installing over an older version: 1.18 introduces significant index formats changes to support optional character case and diacritics sensitivity, and it will be advisable to reset the index in most cases. This will be best done by destroying the index directory (rm -rf ~/.recoll/xapiandb).
If 1.18 is not configured for case and diacritics sensitivity, it is mostly compatible with 1.17 indexes.

Case/diacritics sensitivity is off by default for this release. It can be turned on only by editing recoll.conf ( see the manual). If you do so, you must then reset the index.

Always reset the index if installing over an even older version (1.16 and older). The simplest way to do this is to quit all recoll programs and just delete the index directory (rm -rf ~/.recoll/xapiandb), then start recoll or recollindex. recollindex -z  will do the same in most, but not all, cases.

The subdirectories of xapiandb which were previously used to store the stem expansion database (stem_english, stem_french...) are not used anymore, because the data is now stored in the Xapian synonyms table. They will stay around if you do nothing about them, so you may want to delete them if you have not chosen to just delete the whole index directory.

Viewer exceptions: There is a new list of mime types that should be opened with the locally configured application even when Use Desktop Preferences is checked. This allows making use of new functions (direct access to page), which could not be available through the desktop's xdg-open. The default list contains PDF, Postscript and DVI, which should be opened with the evince (or atril for Mint/MATE users) viewer for the page access functions to work. If you want to keep the previous behaviour (losing the page number functionality), you need to prune the list after installation . This can be done from the Preferences->Gui Configuration menu.

Changes

Recoll 1.18 has some major changes, the most visible of which is the ability to search for exact matches of character case and diacritics.