diff --git a/bundles/org.openhab.ui/web/src/components/pagedesigner/sitemap/widget-details.vue b/bundles/org.openhab.ui/web/src/components/pagedesigner/sitemap/widget-details.vue
index 829462130a..c6d870144a 100644
--- a/bundles/org.openhab.ui/web/src/components/pagedesigner/sitemap/widget-details.vue
+++ b/bundles/org.openhab.ui/web/src/components/pagedesigner/sitemap/widget-details.vue
@@ -24,7 +24,7 @@
           <f7-list-input v-if="supports('encoding')" label="Encoding" type="text" :value="widget.config.encoding" @input="updateParameter('encoding', $event)" clear-button />
           <f7-list-input v-if="supports('service')" label="Service" type="text" :value="widget.config.service" @input="updateParameter('service', $event)" clear-button />
           <f7-list-input v-if="supports('period')" label="Period" type="text"
-                         placeholder="PnYnMnDTnHnMnS" pattern="^P(\d+Y)?(\d+M)?(\d+W)?(\d+D)?(T(\d+H)?(\d+M)?(\d+S)?)?$|^\d*[YMWDh]$" validate validate-on-blur
+                         placeholder="PnYnMnDTnHnMnS" validate pattern="^P(\d+Y)?(\d+M)?(\d+W)?(\d+D)?(T(\d+H)?(\d+M)?(\d+S)?)?$|^\d*[YMWDh]$"
                          :value="widget.config.period" @input="updateParameter('period', $event)" clear-button />
           <f7-list-input v-if="supports('height')" label="Height" type="number" :value="widget.config.height" @input="updateParameter('height', $event)" clear-button />
           <f7-list-input v-if="supports('sendFrequency')" label="Frequency" type="number" :value="widget.config.sendFrequency" @input="updateParameter('sendFrequency', $event)" clear-button />