diff --git a/tests/php/Unit/Collaboration/Collaborators/ManualPhonePluginTest.php b/tests/php/Unit/Collaboration/Collaborators/ManualPhonePluginTest.php
index 965487a72b..6f00def38f 100644
--- a/tests/php/Unit/Collaboration/Collaborators/ManualPhonePluginTest.php
+++ b/tests/php/Unit/Collaboration/Collaborators/ManualPhonePluginTest.php
@@ -17,14 +17,16 @@
 use PHPUnit\Framework\TestCase;
 
 class ManualPhonePluginTest extends TestCase {
-	#[DataProvider('providerSearchScenarios')]
-	public function testSearchReturnsManualEntryOnlyWhenValid(
+	#[DataProvider('providerValidPhoneNumbers')]
+	public function testSearchAddsAnExactManualEntryForAValidPhoneNumber(
 		string $method,
+		string $search,
 		string $rawSearch,
-		?string $normalized,
+		string $expectedRawSearch,
 		string $defaultRegion,
-		?string $expectedRegionParam,
-		int $expectedCount,
+		?string $expectedRegion,
+		string $standardFormat,
+		string $expectedShareWith,
 	): void {
 		$config = $this->createMock(IConfig::class);
 		$config->method('getSystemValueString')
@@ -32,60 +34,150 @@ public function testSearchReturnsManualEntryOnlyWhenValid(
 			->willReturn($defaultRegion);
 
 		$phoneUtil = $this->createMock(IPhoneNumberUtil::class);
-		$phoneUtil->method('convertToStandardFormat')
-			->with($rawSearch, $expectedRegionParam)
-			->willReturn($normalized);
+		$phoneUtil->expects($this->once())
+			->method('convertToStandardFormat')
+			->with($expectedRawSearch, $expectedRegion)
+			->willReturn($standardFormat);
 
 		$context = new SignerSearchContext();
-		$context->set($method, $normalized ?? '', $rawSearch);
+		$context->set($method, $search, $rawSearch);
 
 		$plugin = new ManualPhonePlugin($config, $phoneUtil, $context);
 
 		$searchResult = new SearchResult();
-		$plugin->search($normalized ?? '', 10, 0, $searchResult);
+		$hasMore = $plugin->search($search, 10, 0, $searchResult);
 
 		$results = $searchResult->asArray();
-		$items = array_merge($results['manual-phone'] ?? [], $results['exact']['manual-phone'] ?? []);
-		$this->assertCount($expectedCount, $items);
-		if ($expectedCount > 0) {
-			$this->assertSame(ManualPhonePlugin::TYPE_SIGNER_MANUAL_PHONE, $items[0]['value']['shareType']);
-			$this->assertSame($normalized, $items[0]['value']['shareWith']);
-		}
+		$exact = $results['exact']['manual-phone'] ?? [];
+		$wide = $results['manual-phone'] ?? [];
+
+		$this->assertFalse($hasMore, 'The manual entry is the only result this plugin can offer');
+		$this->assertEmpty($wide, 'A manual entry is always an exact match');
+		$this->assertCount(1, $exact);
+		$this->assertSame($expectedShareWith, $exact[0]['label']);
+		$this->assertSame($expectedShareWith, $exact[0]['shareWithDisplayNameUnique']);
+		$this->assertSame($method, $exact[0]['method']);
+		$this->assertSame($expectedShareWith, $exact[0]['value']['shareWith']);
+		$this->assertSame(ManualPhonePlugin::TYPE_SIGNER_MANUAL_PHONE, $exact[0]['value']['shareType']);
+	}
+
+	#[DataProvider('providerSearchesWithoutAPhoneNumberToValidate')]
+	public function testSearchDoesNotValidateWhenThereIsNoPhoneNumberToOffer(
+		string $method,
+		string $search,
+		string $contextSearch,
+		string $rawSearch,
+	): void {
+		$config = $this->createMock(IConfig::class);
+		$config->expects($this->never())
+			->method('getSystemValueString');
+
+		$phoneUtil = $this->createMock(IPhoneNumberUtil::class);
+		$phoneUtil->expects($this->never())
+			->method('convertToStandardFormat');
+
+		$context = new SignerSearchContext();
+		$context->set($method, $contextSearch, $rawSearch);
+
+		$plugin = new ManualPhonePlugin($config, $phoneUtil, $context);
+
+		$searchResult = new SearchResult();
+		$hasMore = $plugin->search($search, 10, 0, $searchResult);
+
+		$results = $searchResult->asArray();
+
+		$this->assertFalse($hasMore);
+		$this->assertEmpty($results['exact']['manual-phone'] ?? []);
+		$this->assertEmpty($results['manual-phone'] ?? []);
+	}
+
+	public function testSearchDoesNotOfferANumberRejectedByThePhoneNumberUtil(): void {
+		$config = $this->createMock(IConfig::class);
+		$config->method('getSystemValueString')
+			->with('default_phone_region', '')
+			->willReturn('BR');
+
+		$phoneUtil = $this->createMock(IPhoneNumberUtil::class);
+		$phoneUtil->expects($this->once())
+			->method('convertToStandardFormat')
+			->with('123', 'BR')
+			->willReturn(null);
+
+		$context = new SignerSearchContext();
+		$context->set('sms', '123', '123');
+
+		$plugin = new ManualPhonePlugin($config, $phoneUtil, $context);
+
+		$searchResult = new SearchResult();
+		$hasMore = $plugin->search('123', 10, 0, $searchResult);
+
+		$results = $searchResult->asArray();
+
+		$this->assertFalse($hasMore);
+		$this->assertEmpty($results['exact']['manual-phone'] ?? []);
+		$this->assertEmpty($results['manual-phone'] ?? []);
 	}
 
-	public static function providerSearchScenarios(): array {
+	public static function providerValidPhoneNumbers(): array {
 		return [
-			'non phone method' => [
-				'method' => 'email',
+			'national number with a default region' => [
+				'method' => 'whatsapp',
+				'search' => '+5521987654321',
 				'rawSearch' => '21987654321',
-				'normalized' => '+5521987654321',
+				'expectedRawSearch' => '21987654321',
 				'defaultRegion' => 'BR',
-				'expectedRegionParam' => 'BR',
-				'expectedCount' => 0,
+				'expectedRegion' => 'BR',
+				'standardFormat' => '+5521987654321',
+				'expectedShareWith' => '+5521987654321',
 			],
-			'invalid number' => [
+			'e164 number without a default region' => [
 				'method' => 'sms',
-				'rawSearch' => '123',
-				'normalized' => null,
+				'search' => '+12025551234',
+				'rawSearch' => '+12025551234',
+				'expectedRawSearch' => '+12025551234',
+				'defaultRegion' => '',
+				'expectedRegion' => null,
+				'standardFormat' => '+12025551234',
+				'expectedShareWith' => '+12025551234',
+			],
+			'surrounding whitespace is discarded' => [
+				'method' => 'signal',
+				'search' => '  +5521987654321  ',
+				'rawSearch' => "\t21987654321 ",
+				'expectedRawSearch' => '21987654321',
 				'defaultRegion' => 'BR',
-				'expectedRegionParam' => 'BR',
-				'expectedCount' => 0,
+				'expectedRegion' => 'BR',
+				'standardFormat' => '+55 21 98765-4321',
+				'expectedShareWith' => '+5521987654321',
 			],
-			'valid number' => [
-				'method' => 'whatsapp',
+		];
+	}
+
+	public static function providerSearchesWithoutAPhoneNumberToValidate(): array {
+		return [
+			'method that does not use a phone number' => [
+				'method' => 'email',
+				'search' => '+5521987654321',
+				'contextSearch' => '+5521987654321',
 				'rawSearch' => '21987654321',
-				'normalized' => '+5521987654321',
-				'defaultRegion' => 'BR',
-				'expectedRegionParam' => 'BR',
-				'expectedCount' => 1,
 			],
-			'valid e164 without default region' => [
+			'empty search' => [
 				'method' => 'sms',
-				'rawSearch' => '+12025551234',
-				'normalized' => '+12025551234',
-				'defaultRegion' => '',
-				'expectedRegionParam' => null,
-				'expectedCount' => 1,
+				'search' => '',
+				'contextSearch' => '',
+				'rawSearch' => '21987654321',
+			],
+			'search made only of whitespace' => [
+				'method' => 'sms',
+				'search' => '   ',
+				'contextSearch' => '   ',
+				'rawSearch' => '21987654321',
+			],
+			'context without the raw search typed by the user' => [
+				'method' => 'sms',
+				'search' => '+5521987654321',
+				'contextSearch' => '',
+				'rawSearch' => '',
 			],
 		];
 	}