diff --git a/pg-act/reg/ds.php b/pg-act/reg/ds.php
index bbfd326..bb4168e 100644
--- a/pg-act/reg/ds.php
+++ b/pg-act/reg/ds.php
@@ -13,12 +13,12 @@ if ($_POST['dt'] !== '2' AND $_POST['dt'] !== '4')
 if (preg_match('/^(?:[0-9a-fA-F]{64}|[0-9a-fA-F]{96})$/D', $_POST['key']) !== 1)
 	output(403, 'Wrong value for <code>key</code>.');
 
-regCheckDomainPossession($_POST['zone']);
+regCheckDomainPossession($_POST['domain']);
 
 rateLimit();
 
-knotcZoneExec(regParseDomain($_POST['zone'])['suffix'], [
-	$_POST['zone'],
+knotcZoneExec(regParseDomain($_POST['domain'])['suffix'], [
+	$_POST['domain'],
 	CONF['reg']['ttl'],
 	'DS',
 	$_POST['keytag'],
diff --git a/pg-act/reg/glue.php b/pg-act/reg/glue.php
index 3ceecf9..a7a8ca9 100644
--- a/pg-act/reg/glue.php
+++ b/pg-act/reg/glue.php
@@ -1,11 +1,11 @@
 <?php
 
-regCheckDomainPossession($_POST['suffix']);
+regCheckDomainPossession($_POST['domain']);
 
 rateLimit();
 
-knotcZoneExec(regParseDomain($_POST['suffix'])['suffix'], [
-	formatAbsoluteDomain(formatEndWithDot($_POST['subdomain']) . $_POST['suffix']),
+knotcZoneExec(regParseDomain($_POST['domain'])['suffix'], [
+	formatAbsoluteDomain(formatEndWithDot($_POST['subdomain']) . $_POST['domain']),
 	CONF['reg']['ttl'],
 	checkIpFormat($_POST['ip']),
 	$_POST['ip']
diff --git a/pg-view/ns/form.ns.php b/pg-view/ns/form.ns.php
index 5f18f7f..3c05c42 100644
--- a/pg-view/ns/form.ns.php
+++ b/pg-view/ns/form.ns.php
@@ -1,7 +1,7 @@
 	<label for="action"><?= _('Action') ?></label>
 	<select name="action" id="action">
-		<option value="add"><?= _('Add') ?></option>
-		<option value="delete"><?= _('Delete') ?></option>
+		<option value="add"<?= ($_POST['action'] ?? NULL) === 'add' ? ' selected=""' : '' ?>><?= _('Add') ?></option>
+		<option value="delete"<?= ($_POST['action'] ?? NULL) === 'delete' ? ' selected=""' : '' ?>><?= _('Delete') ?></option>
 	</select>
 
 	<fieldset>
@@ -9,18 +9,19 @@
 		<div>
 			<label for="subdomain"><?= _('Subdomain') ?></label>
 			<br>
-			<input id="subdomain" size="16" placeholder="www" pattern="^(([a-z0-9_-]{1,63}\.?){1,127})|(@){1}$" name="subdomain" type="text">
+			<input id="subdomain" size="16" placeholder="www" pattern="^(([a-z0-9_-]{1,63}\.?){1,127})|(@){1}$" name="subdomain" type="text" value="<?= htmlspecialchars($_POST['subdomain'] ?? '') ?>">
 		</div>
 		<div>
 			<label for="zone"><?= _('Zone') ?></label>
 			<br>
 			<select required="" name="zone" id="zone">
-				<option value="" disabled="" selected="">—</option>
 <?php
-foreach (nsListUserZones() as $zone)
-	echo "<option value='" . $zone . "'>" . $zone . "</option>";
+$user_zones = nsListUserZones();
+if (!in_array($_POST['zone'] ?? NULL, $user_zones, true))
+	echo '				<option value="" disabled="" selected="">—</option>' . LF;
+foreach ($user_zones as $zone)
+	echo '				<option value="' . $zone . '"' . (($_POST['zone'] ?? NULL) === $zone ? ' selected=""' : '') . '>.' . $zone . '</option>' . LF;
 ?>
-
 			</select>
 		</div>
 	</fieldset>
@@ -30,7 +31,7 @@ foreach (nsListUserZones() as $zone)
 		<div>
 			<label for="ttl-value"><?= _('Value') ?></label>
 			<br>
-			<input required="" id="ttl-value" list="ttls" name="ttl-value" size="6" type="number" min="1" max="432000" value="<?= DEFAULT_TTL ?>" placeholder="<?= DEFAULT_TTL ?>">
+			<input required="" id="ttl-value" list="ttls" name="ttl-value" size="6" type="number" min="1" max="432000" value="<?= $_POST['ttl-value'] ?? DEFAULT_TTL ?>" placeholder="<?= DEFAULT_TTL ?>">
 			<datalist id="ttls">
 				<option value="900">
 				<option value="1800">
@@ -45,10 +46,10 @@ foreach (nsListUserZones() as $zone)
 			<label for="ttl-multiplier"><?= _('Unit') ?></label>
 			<br>
 			<select required="" name="ttl-multiplier" id="ttl-multiplier">
-				<option value="1"><?= _('second') ?></option>
-				<option value="60"><?= _('minute') ?></option>
-				<option value="3600"><?= _('hour') ?></option>
-				<option value="86400"><?= _('day') ?></option>
+				<option value="1"<?= ($_POST['ttl-multiplier'] ?? NULL) === '1' ? ' selected=""' : '' ?>><?= _('second') ?></option>
+				<option value="60"<?= ($_POST['ttl-multiplier'] ?? NULL) === '60' ? ' selected=""' : '' ?>><?= _('minute') ?></option>
+				<option value="3600"<?= ($_POST['ttl-multiplier'] ?? NULL) === '3600' ? ' selected=""' : '' ?>><?= _('hour') ?></option>
+				<option value="86400"<?= ($_POST['ttl-multiplier'] ?? NULL) === '86400' ? ' selected=""' : '' ?>><?= _('day') ?></option>
 			</select>
 		</div>
 	</fieldset>
diff --git a/pg-view/reg/ds.php b/pg-view/reg/ds.php
index ef1a6ae..7338136 100644
--- a/pg-view/reg/ds.php
+++ b/pg-view/reg/ds.php
@@ -1,19 +1,7 @@
 <form method="post">
-	<label for="action"><?= _('Action') ?></label>
-	<select name="action" id="action">
-		<option value="add"><?= _('Add') ?></option>
-		<option value="delete"><?= _('Delete') ?></option>
-	</select>
+<?php require ROOT_PATH . '/pg-view/reg/select-action.inc.php'; ?>
 	<br>
-	<label for="zone"><?= _('Domain') ?></label>
-	<br>
-	<select required="" name="zone" id="zone">
-		<option value="" disabled="" selected="">—</option>
-<?php
-foreach (regListUserDomains() as $domain)
-	echo '		<option value="' . $domain . '">' . $domain . '</option>' . LF;
-?>
-	</select>
+<?php require ROOT_PATH . '/pg-view/reg/select-domain.inc.php'; ?>
 	<br>
 	<label for="keytag"><?= _('Key tag') ?></label>
 	<br>
diff --git a/pg-view/reg/glue.php b/pg-view/reg/glue.php
index d1aab56..44ca00a 100644
--- a/pg-view/reg/glue.php
+++ b/pg-view/reg/glue.php
@@ -1,9 +1,5 @@
 <form method="post">
-	<label for="action"><?= _('Action') ?></label>
-	<select name="action" id="action">
-		<option value="add"><?= _('Add') ?></option>
-		<option value="delete"><?= _('Delete') ?></option>
-	</select>
+<?php require ROOT_PATH . '/pg-view/reg/select-action.inc.php'; ?>
 	<fieldset>
 		<legend><?= _('Domain') ?></legend>
 		<div>
@@ -12,15 +8,7 @@
 			<input required="" id="subdomain" placeholder="ns1" name="subdomain" type="text">
 		</div>
 		<div>
-			<label for="suffix"><?= _('Domain') ?></label>
-			<br>
-			<select required="" name="suffix" id="suffix">
-				<option value="" disabled="" selected="">—</option>
-<?php
-foreach (regListUserDomains() as $suffix)
-	echo '		<option value="' . $suffix . '">' . $suffix . '</option>' . LF;
-?>
-			</select>
+<?php require ROOT_PATH . '/pg-view/reg/select-domain.inc.php'; ?>
 		</div>
 	</fieldset>
 	<label for="ip"><?= _('IP address') ?></label><br>
diff --git a/pg-view/reg/ns.php b/pg-view/reg/ns.php
index 2315f05..b092e63 100644
--- a/pg-view/reg/ns.php
+++ b/pg-view/reg/ns.php
@@ -1,19 +1,7 @@
 <form method="post">
-	<label for="action"><?= _('Action') ?></label>
-	<select name="action" id="action">
-		<option value="add"><?= _('Add') ?></option>
-		<option value="delete"><?= _('Delete') ?></option>
-	</select>
+<?php require ROOT_PATH . '/pg-view/reg/select-action.inc.php'; ?>
 	<br>
-	<label for="domain"><?= _('Domain') ?></label>
-	<br>
-	<select required="" name="domain" id="domain">
-		<option value="" disabled="" selected="">—</option>
-<?php
-foreach (regListUserDomains() as $domain)
-	echo '		<option value="' . $domain . '">' . $domain . '</option>' . LF;
-?>
-	</select>
+<?php require ROOT_PATH . '/pg-view/reg/select-domain.inc.php'; ?>
 	<br>
 	<label for="ns"><?= _('Name server') ?></label>
 	<br>
diff --git a/pg-view/reg/print.php b/pg-view/reg/print.php
index bddca80..f59c6f4 100644
--- a/pg-view/reg/print.php
+++ b/pg-view/reg/print.php
@@ -1,12 +1,5 @@
 <form method="post">
-	<label for="domain"><?= _('Domain') ?></label>
-	<select required="" name="domain" id="domain">
-		<option value="" disabled="" selected="">-</option>
-<?php
-foreach (regListUserDomains() as $domain)
-	echo '		<option value="' . $domain . '">' . $domain . '</option>' . LF;
-?>
-	</select>
+<?php require ROOT_PATH . '/pg-view/reg/select-domain.inc.php'; ?>
 	<br>
 	<input type="submit" value="<?= _('Display') ?>">
 </form>
diff --git a/pg-view/reg/select-action.inc.php b/pg-view/reg/select-action.inc.php
new file mode 100644
index 0000000..cfc5d3c
--- /dev/null
+++ b/pg-view/reg/select-action.inc.php
@@ -0,0 +1,5 @@
+	<label for="action"><?= _('Action') ?></label>
+	<select name="action" id="action">
+		<option value="add"<?= ($_POST['action'] ?? NULL) === 'add' ? ' selected=""' : '' ?>><?= _('Add') ?></option>
+		<option value="delete"<?= ($_POST['action'] ?? NULL) === 'delete' ? ' selected=""' : '' ?>><?= _('Delete') ?></option>
+	</select>
diff --git a/pg-view/reg/select-domain.inc.php b/pg-view/reg/select-domain.inc.php
new file mode 100644
index 0000000..0902483
--- /dev/null
+++ b/pg-view/reg/select-domain.inc.php
@@ -0,0 +1,11 @@
+	<label for="domain"><?= _('Domain') ?></label>
+	<br>
+	<select required="" name="domain" id="domain">
+<?php
+$user_domains = regListUserDomains();
+if (!in_array($_POST['domain'] ?? NULL, $user_domains, true))
+	echo '		<option value="" disabled="" selected="">—</option>' . LF;
+foreach ($user_domains as $domain)
+	echo '		<option value="' . $domain . '"' . (($_POST['domain'] ?? NULL === $domain) ? ' selected=""' : '') . '>' . $domain . '</option>' . LF;
+?>
+	</select>