Thx for your reply,
My access rights are identical... :(
Here is the log may be it can help to find the solution :
2019-02-04 23:27:07,218 1 INFO db_odoo_12 werkzeug: 172.18.0.1 - - [04/Feb/2019 23:27:07] "POST /web/dataset/call_kw/event.event/default_get HTTP/1.1" 200 - 5 0.003 0.007
2019-02-04 23:27:07,238 1 INFO db_odoo_12 werkzeug: 172.18.0.1 - - [04/Feb/2019 23:27:07] "POST /web/dataset/call_kw/event.event/onchange HTTP/1.1" 200 - 2 0.001 0.009
2019-02-04 23:27:07,265 1 INFO db_odoo_12 werkzeug: 172.18.0.1 - - [04/Feb/2019 23:27:07] "POST /web/dataset/call_kw/res.partner/name_get HTTP/1.1" 200 - 6 0.007 0.011
2019-02-04 23:27:07,272 1 INFO db_odoo_12 werkzeug: 172.18.0.1 - - [04/Feb/2019 23:27:07] "POST /web/dataset/call_kw/res.partner/name_get HTTP/1.1" 200 - 6 0.007 0.016
2019-02-04 23:27:07,284 1 INFO db_odoo_12 werkzeug: 172.18.0.1 - - [04/Feb/2019 23:27:07] "POST /web/dataset/call_kw/res.company/name_get HTTP/1.1" 200 - 10 0.020 0.013
2019-02-04 23:27:07,291 1 INFO db_odoo_12 werkzeug: 172.18.0.1 - - [04/Feb/2019 23:27:07] "POST /web/dataset/call_kw/res.users/name_get HTTP/1.1" 200 - 14 0.009 0.028
2019-02-04 23:27:19,957 1 INFO db_odoo_12 werkzeug: 172.18.0.1 - - [04/Feb/2019 23:27:19] "POST /web/dataset/call_kw/event.event/onchange HTTP/1.1" 200 - 1 0.000 0.007
2019-02-04 23:27:20,070 1 INFO db_odoo_12 werkzeug: 172.18.0.1 - - [04/Feb/2019 23:27:20] "POST /web/dataset/call_kw/event.event/onchange HTTP/1.1" 200 - 1 0.000 0.005
2019-02-04 23:27:21,489 1 INFO db_odoo_12 werkzeug: 172.18.0.1 - - [04/Feb/2019 23:27:21] "POST /web/dataset/call_kw/event.type/name_search HTTP/1.1" 200 - 5 0.004 0.007
2019-02-04 23:27:22,340 1 INFO db_odoo_12 werkzeug: 172.18.0.1 - - [04/Feb/2019 23:27:22] "POST /web/dataset/call_kw/event.event/onchange HTTP/1.1" 200 - 9 0.009 0.011
2019-02-04 23:27:27,862 1 INFO db_odoo_12 werkzeug: 172.18.0.1 - - [04/Feb/2019 23:27:27] "POST /longpolling/poll HTTP/1.1" 200 - 8 0.002 50.010
2019-02-04 23:27:34,963 1 INFO db_odoo_12 werkzeug: 172.18.0.1 - - [04/Feb/2019 23:27:34] "POST /web/dataset/call_kw/event.event.ticket/default_get HTTP/1.1" 200 - 5 0.002 0.005
2019-02-04 23:27:34,985 1 INFO db_odoo_12 odoo.models: Impossible d'effectuer l'opération demandée, en raison des règles d'enregistrement : Type de document : product.product, Opération : read, Enregistrements : 39, Utilisateur : 2
2019-02-04 23:27:34,986 1 INFO db_odoo_12 odoo.models: Impossible d'effectuer l'opération demandée, en raison des règles d'enregistrement : Type de document : product.product, Opération : read, Enregistrements : 39, Utilisateur : 2
2019-02-04 23:27:34,988 1 INFO db_odoo_12 werkzeug: 172.18.0.1 - - [04/Feb/2019 23:27:34] "POST /web/dataset/call_kw/event.event.ticket/onchange HTTP/1.1" 200 - 14 0.009 0.010
2019-02-04 23:27:35,009 1 INFO db_odoo_12 werkzeug: 172.18.0.1 - - [04/Feb/2019 23:27:35] "POST /web/dataset/call_kw/product.product/name_get HTTP/1.1" 200 - 9 0.006 0.008
The problem can easely reproduced by creating a second company and create an event while it is selected (on the right of the top menu).
Thx for your help.
Daniel