diff --git a/LibreNMS/OS/Symbol.php b/LibreNMS/OS/Symbol.php
index 071fd11612..dd386c7a7c 100644
--- a/LibreNMS/OS/Symbol.php
+++ b/LibreNMS/OS/Symbol.php
@@ -41,7 +41,7 @@ class Symbol extends OS implements WirelessClientsDiscovery
     {
         $device = $this->getDevice();
 
-        if (str_contains($device['hardware'], 'AP', true)) {
+        if (str_i_contains($device['hardware'], 'AP')) {
             $oid = '.1.3.6.1.4.1.388.11.2.4.2.100.10.1.18.1';
             return array(
                 new WirelessSensor('clients', $device['device_id'], $oid, 'symbol', 1, 'Clients')
diff --git a/html/ajax_rulesuggest.php b/html/ajax_rulesuggest.php
index 094d957d52..f6ec6e3c9b 100644
--- a/html/ajax_rulesuggest.php
+++ b/html/ajax_rulesuggest.php
@@ -123,7 +123,7 @@ if (isset($_GET['term'], $_GET['device_id'])) {
 } elseif ($vars['type'] === 'alert_rule_collection') {
     $x=0;
     foreach (get_rules_from_json() as $rule) {
-        if (str_contains($rule['name'], $vars['term'], true)) {
+        if (str_i_contains($rule['name'], $vars['term'])) {
             $rule['id'] = $x;
             $tmp[] = $rule;
         }
diff --git a/includes/common.php b/includes/common.php
index cb7ed8cd92..4d58f60aa4 100644
--- a/includes/common.php
+++ b/includes/common.php
@@ -1385,83 +1385,78 @@ function ResolveGlues($tables, $target, $x = 0, $hist = array(), $last = array()
     return false;
 }
 
+if (!function_exists('str_contains')) {
+    /**
+     * Determine if a given string contains a given substring.
+     *
+     * @param  string $haystack
+     * @param  string|array $needles
+     * @return bool
+     */
+    function str_contains($haystack, $needles)
+    {
+        foreach ((array)$needles as $needle) {
+            if ($needle != '' && strpos($haystack, $needle) !== false) {
+                return true;
+            }
+        }
+        return false;
+    }
+}
+
 /**
  * Determine if a given string contains a given substring.
  *
  * @param  string $haystack
  * @param  string|array $needles
- * @param  bool $case_insensitive
  * @return bool
  */
-function str_contains($haystack, $needles, $case_insensitive = false)
+function str_i_contains($haystack, $needles)
 {
-    if ($case_insensitive) {
-        foreach ((array) $needles as $needle) {
-            if ($needle != '' && stripos($haystack, $needle) !== false) {
-                return true;
-            }
-        }
-    } else {
-        foreach ((array) $needles as $needle) {
-            if ($needle != '' && strpos($haystack, $needle) !== false) {
-                return true;
-            }
+    foreach ((array)$needles as $needle) {
+        if ($needle != '' && stripos($haystack, $needle) !== false) {
+            return true;
         }
     }
     return false;
 }
 
-/**
- * Determine if a given string ends with a given substring.
- *
- * @param  string $haystack
- * @param  string|array $needles
- * @param  bool $case_insensitive
- * @return bool
- */
-function ends_with($haystack, $needles, $case_insensitive = false)
-{
-    if ($case_insensitive) {
-        $lower_haystack = strtolower($haystack);
-        foreach ((array)$needles as $needle) {
-            if (strtolower($needle) === substr($lower_haystack, -strlen($needle))) {
-                return true;
-            }
-        }
-    } else {
+if (!function_exists('ends_with')) {
+    /**
+     * Determine if a given string ends with a given substring.
+     *
+     * @param  string $haystack
+     * @param  string|array $needles
+     * @return bool
+     */
+    function ends_with($haystack, $needles)
+    {
         foreach ((array)$needles as $needle) {
             if ((string)$needle === substr($haystack, -strlen($needle))) {
                 return true;
             }
         }
+        return false;
     }
-    return false;
 }
 
-/**
- * Determine if a given string starts with a given substring.
- *
- * @param  string $haystack
- * @param  string|array $needles
- * @param  bool $case_insensitive
- * @return bool
- */
-function starts_with($haystack, $needles, $case_insensitive = false)
-{
-    if ($case_insensitive) {
-        foreach ((array)$needles as $needle) {
-            if ($needle != '' && stripos($haystack, $needle) === 0) {
-                return true;
-            }
-        }
-    } else {
+if (!function_exists('starts_with')) {
+    /**
+     * Determine if a given string starts with a given substring.
+     *
+     * @param  string $haystack
+     * @param  string|array $needles
+     * @return bool
+     */
+    function starts_with($haystack, $needles)
+    {
         foreach ((array)$needles as $needle) {
             if ($needle != '' && strpos($haystack, $needle) === 0) {
                 return true;
             }
         }
+        return false;
     }
-    return false;
 }
 
 function get_auth_ad_user_filter($username)
diff --git a/includes/discovery/functions.inc.php b/includes/discovery/functions.inc.php
index a8fd43e1f5..025863232c 100644
--- a/includes/discovery/functions.inc.php
+++ b/includes/discovery/functions.inc.php
@@ -1005,7 +1005,7 @@ function discovery_process(&$valid, $device, $sensor_type, $pre_cache)
                 if (!is_numeric($tmp_value)) {
                     if ($sensor_type === 'temperature') {
                         // For temp sensors, try and detect fahrenheit values
-                        if (ends_with($tmp_value, 'f', true)) {
+                        if (ends_with($tmp_value, array('f', 'F'))) {
                             $user_function = 'fahrenheit_to_celsius';
                         }
                     }
diff --git a/includes/functions.php b/includes/functions.php
index b411167cc0..126b764c64 100644
--- a/includes/functions.php
+++ b/includes/functions.php
@@ -1069,12 +1069,12 @@ function is_port_valid($port, $device)
     $ifAlias = $port['ifAlias'];
     $ifType  = $port['ifType'];
 
-    if (str_contains($ifDescr, Config::getOsSetting($device['os'], 'good_if'), true)) {
+    if (str_i_contains($ifDescr, Config::getOsSetting($device['os'], 'good_if'))) {
         return true;
     }
 
     foreach (Config::getCombined($device['os'], 'bad_if') as $bi) {
-        if (str_contains($ifDescr, $bi, true)) {
+        if (str_i_contains($ifDescr, $bi)) {
             d_echo("ignored by ifDescr: $ifDescr (matched: $bi)\n");
             return false;
         }
diff --git a/includes/polling/functions.inc.php b/includes/polling/functions.inc.php
index 10ccbd1647..8931ba001a 100644
--- a/includes/polling/functions.inc.php
+++ b/includes/polling/functions.inc.php
@@ -420,7 +420,7 @@ function poll_mib_def($device, $mib_name_table, $mib_subdir, $mib_oids, $mib_gra
     list($mib, $file) = explode(':', $mib_name_table, 2);
 
     if (is_null($rrd_name)) {
-        if (str_contains($mib_name_table, 'UBNT', true)) {
+        if (str_i_contains($mib_name_table, 'UBNT')) {
             $rrd_name = strtolower($mib);
         } else {
             $rrd_name = strtolower($file);
diff --git a/scripts/new-os.php b/scripts/new-os.php
index e37e0f7dfd..73f9f19990 100755
--- a/scripts/new-os.php
+++ b/scripts/new-os.php
@@ -44,7 +44,7 @@ sysObjectID: $full_sysObjectID
             $continue = get_user_input("We already detect this device as OS $os type, do you want to continue to add sensors? (Y/n)");
         }
 
-        if (!str_contains($continue, 'y', true)) {
+        if (!str_i_contains($continue, 'y')) {
             $descr = get_user_input('Enter the description for this OS, i.e Cisco IOS:');
             $icon = get_user_input('Enter the logo to use, this can be the name of an existing one (i.e: cisco) or the url to retrieve one:');
 
diff --git a/tests/CommonFunctionsTest.php b/tests/CommonFunctionsTest.php
index 8acf11849a..f065fb00d9 100644
--- a/tests/CommonFunctionsTest.php
+++ b/tests/CommonFunctionsTest.php
@@ -34,14 +34,14 @@ class CommonFunctionsTest extends TestCase
         $this->assertTrue(str_contains($data, 'Just'));
         $this->assertFalse(str_contains($data, 'just'));
 
-        $this->assertTrue(str_contains($data, 'juSt', true));
-        $this->assertFalse(str_contains($data, 'nope', true));
+        $this->assertTrue(str_i_contains($data, 'juSt'));
+        $this->assertFalse(str_i_contains($data, 'nope'));
 
         $this->assertTrue(str_contains($data, array('not', 'this', 'This')));
         $this->assertFalse(str_contains($data, array('not', 'this')));
 
-        $this->assertTrue(str_contains($data, array('not', 'thIs'), true));
-        $this->assertFalse(str_contains($data, array('not', 'anything'), true));
+        $this->assertTrue(str_i_contains($data, array('not', 'thIs')));
+        $this->assertFalse(str_i_contains($data, array('not', 'anything')));
     }
 
     public function testStartsWith()
@@ -51,14 +51,8 @@ class CommonFunctionsTest extends TestCase
         $this->assertTrue(starts_with($data, 'This'));
         $this->assertFalse(starts_with($data, 'this'));
 
-        $this->assertTrue(starts_with($data, 'thIs', true));
-        $this->assertFalse(starts_with($data, 'test', true));
-
         $this->assertTrue(starts_with($data, array('this', 'Test', 'This')));
         $this->assertFalse(starts_with($data, array('this', 'Test')));
-
-        $this->assertTrue(starts_with($data, array('Test', 'no', 'thiS'), true));
-        $this->assertFalse(starts_with($data, array('just', 'Test'), true));
     }
 
     public function testEndsWith()
@@ -68,14 +62,8 @@ class CommonFunctionsTest extends TestCase
         $this->assertTrue(ends_with($data, 'Testing'));
         $this->assertFalse(ends_with($data, 'testing'));
 
-        $this->assertTrue(ends_with($data, 'testIng', true));
-        $this->assertFalse(ends_with($data, 'test', true));
-
         $this->assertTrue(ends_with($data, array('this', 'Testing', 'This')));
         $this->assertFalse(ends_with($data, array('this', 'Test')));
-
-        $this->assertTrue(ends_with($data, array('this', 'tesTing', 'no'), true));
-        $this->assertFalse(ends_with($data, array('this', 'Test'), true));
     }
 
     public function testRrdDescriptions()