blank backoffice on 1.7.5.0

[SebSept]

I tried the module on a 1.7.5.0 installation.
It was fine until I activated the 'show hooks' option.
I had this in symfony log :

[2021-03-18 16:06:03] doctrine.DEBUG: SELECT name FROM ps_module WHERE active = 1 [] []
[2021-03-18 16:06:04] php.CRITICAL: Call to a member function getImage() on null {"exception":"[object] (Symfony\\Component\\Debug\\Exception\\FatalThrowableError(code: 0): Call to a member function getImage() on null at /home/http/pro/leclient/var/cache/dev/smarty/compile/e0/e7/be/e0e7be1d2e99e7404efbd4f4f8227fde0bfc4bd6_0.file.header.tpl.php:467)"} []
[2021-03-18 16:06:04] doctrine.DEBUG: SELECT name FROM ps_module WHERE active = 1 [] []
[2021-03-18 16:06:04] doctrine.DEBUG: SELECT * from ps_employee [] []
[2021-03-18 16:06:04] request.CRITICAL: Uncaught PHP Exception Symfony\Component\Debug\Exception\FatalThrowableError: "Call to a member function getImage() on null" at /home/http/pro/leclient/var/cache/dev/smarty/compile/e0/e7/be/e0e7be1d2e99e7404efbd4f4f8227fde0bfc4bd6_0.file.header.tpl.php line 467 {"exception":"[object] (Symfony\\Component\\Debug\\Exception\\FatalThrowableError(code: 0): Call to a member function getImage() on null at /home/http/pro/leclient/var/cache/dev/smarty/compile/e0/e7/be/e0e7be1d2e99e7404efbd4f4f8227fde0bfc4bd6_0.file.header.tpl.php:467)"} []
[2021-03-18 16:06:04] php.CRITICAL: Cannot use object of type Symfony\Component\HttpFoundation\ParameterBag as array {"exception":"[object] (Symfony\\Component\\Debug\\Exception\\FatalThrowableError(code: 0): Cannot use object of type Symfony\\Component\\HttpFoundation\\ParameterBag as array at /home/http/pro/leclient/src/Adapter/Security/Admin.php:91)"} []

I checked : the $employee variable is null.
uninstalling the module solved the problem.