fixe multi select

src/app/shared/components/presentationals/shared-searchable-multi-select-content/shared-searchable-multi-select-content.presentational.html

 <form [formGroup]="form"
       [dlcmAutoScrollIntoView]="!navigationResId"
       (keydown.tab)="closeByTab()"
-      (keydown.enter)="select(getFocusedResource)"
       (keydown.shift.tab)="closeByTab()">
   <div class="input">
     <mat-form-field class="form-field">

src/app/shared/components/presentationals/shared-searchable-multi-select-content/shared-searchable-multi-select-content.presentational.ts

@@ -16,6 +16,7 @@ import {
 } from "rxjs";
 import {
   BaseResourceType,
+  isNotNullNorUndefined,
   ObservableUtil,
   ResourceStateModel,
 } from "solidify-frontend";
@@ -44,11 +45,13 @@ export class SharedSearchableMultiSelectContentPresentational<TResource extends
   }
 
   select(value: TResource): void {
-    if (this.isActive(value)) {
-      this._valueRemovedBS.next(value);
-      return;
+    if (isNotNullNorUndefined(value)) {
+      if (this.isActive(value)) {
+        this._valueRemovedBS.next(value);
+        return;
+      }
+      this._valueAddedBS.next(value);
     }
-    this._valueAddedBS.next(value);
   }
 }