Thank you Tony,
I ever tried to clear the cache and I event changed the browser to Chome without success.
here are Jevents support info :
PHP Version : 7.0.27
MySQL Version : 5.7.20-log
Server Information : Linux webd345.cluster020.gra.hosting.ovh.net 4.14.19-ovh-vps-grsec-zfs-classid #1 SMP Thu Feb 15 06:51:19 CET 2018 x86_64
Fix jQuery? : Yes
Load JEvents Bootstrap CSS? : Yes
Club code set? : No
User Agent : Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:58.0) Gecko/20100101 Firefox/58.0
Joomla : 3.8.5
component_com_jevents : 3.4.46
component_com_jce : 2.6.26
component_com_comprofiler : 2.1.4
component_plg_kunena_comprofiler : 5.0.13
module_mod_jevents_cal : 3.4.46
module_mod_jevents_custom : 3.4.46
module_mod_jevents_filter : 3.4.46
module_mod_jevents_latest : 3.4.46
module_mod_jevents_legend : 3.4.46
module_mod_jevents_switchview : 3.4.46
plugin_content_jevents : 3.4.46
plugin_finder_jevents : 3.4.46
plugin_installer_jeventsinstaller : 3.4.46
plugin_kunena_comprofiler : 5.0.13 (not enabled)
plugin_search_eventsearch : 3.4.46
plugin_system_gwejson : 3.4.46
Any other infos ?