Prev/Next month buttons hidden

Hello!

I have a problem that I cannot solve: the prev/next month buttons are hidden, in a menu that displays month view, with the "geraint" theme…
In the JEvents Config page as in the Menu page, whatever I choose "Nav icons" or "Icons without nav" it displays what I should get if I had selected the second one.
Thanks for you help

numero_744

PHP Version : 7.0.0

MySQL Version : 5.5.42

Server Information : Darwin come.home 13.4.0 Darwin Kernel Version 13.4.0: Mon Jan 11 18:17:34 PST 2016; root:xnu-2422.115.15~1/RELEASE_X86_64 x86_64

Fix jQuery? : Yes

Load JEvents Bootstrap CSS? : Yes

Max Input Vars ? : 1000

Club code set? : No  

User Agent : Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:47.0) Gecko/20100101 Firefox/47.0  

Joomla : 3.6.0

component_com_jevents : 3.4.15

module_mod_jevents_cal : 3.4.15

module_mod_jevents_custom : 3.4.15

module_mod_jevents_filter : 3.4.15

module_mod_jevents_latest : 3.4.15

module_mod_jevents_legend : 3.4.15

module_mod_jevents_switchview : 3.4.15

plugin_content_jevents : 3.4.15

plugin_finder_jevents : 3.4.15 (not enabled)

plugin_search_eventsearch : 3.4.15

plugin_system_gwejson : 3.4.15