I found the solution.
As said in the EDIT of my answer, a <div>
is misfunctioning in a <table>
.
So I wrote this code instead :
<tr id="hidden" style="display:none;">
<td class="depot_table_left">
<label for="sexe">Sexe</label>
</td>
<td>
<select type="text" name="sexe">
<option value="1">Sexe</option>
<option value="2">Joueur</option>
<option value="3">Joueuse</option>
</select>
</td>
</tr>
And this is working fine.
Thanks everybody ;)