Arch Linux

Description:

With the upcoming Dovecot 2.4 a new FTS "fts_flatcurve" (based on https://github.com/slusarz/dovecot-fts-flatcurve) will be included in Dovecot core - see https://github.com/dovecot/core/commit/137572e77fdf79b2e8d607021667741ed3f19da1.
I am currently using your package with Dovecot 2.3.x and compile fts_flatcurve against it as described in https://github.com/slusarz/dovecot-fts-flatcurve#compilation.

Applying the recommended defaults in regards to `fts_filters` (https://github.com/slusarz/dovecot-fts-flatcurve#fts-flatcurve-plugin-settings-example or https://doc.dovecot.org/settings/plugin/fts-plugin/#plugin_setting-fts-fts_filters)
then results in this error:

```
Error: fts-flatcurve: fts_filter_snowball: Snowball support not built in
Error: fts: Failed to initialize backend 'flatcurve': fts-flatcurve: Invalid settings
```

This is due to your package not yet building with stemmer support (--with-stemmer) which I'd like to suggest via this bug report.

If I may also point out, that `--with-stemmer` is also recommended for the Lucene FTS plugin (https://doc.dovecot.org/configuration_manual/fts/lucene/), which you do build support for.
But actually this plugin is on the list of deprecated FTS:

* https://doc.dovecot.org/configuration_manual/fts/#deprecated-unmaintained-fts-plugins


Additional info:
* Package version: dovecot-2.3.20-1

Steps to reproduce:

1) Compile fts_flatcurve against the installed Dovecot via
2) App recommended fts_flatcurve config: