diff --git a/modules/juce_core/text/juce_CharacterFunctions.h b/modules/juce_core/text/juce_CharacterFunctions.h
index fde96a0563..4487b09b09 100644
--- a/modules/juce_core/text/juce_CharacterFunctions.h
+++ b/modules/juce_core/text/juce_CharacterFunctions.h
@@ -761,6 +761,36 @@ public:
         return -1;
     }
 
+    /** Given a CharacterPointer range and a predicate, returns a pointer to the first
+        character in the range that does not satisfy the predicate.
+    */
+    template <typename Type, typename Predicate>
+    static Type trimBegin (Type begin, const Type end, Predicate&& shouldTrim)
+    {
+        while (begin != end && shouldTrim (begin))
+            ++begin;
+
+        return begin;
+    }
+
+    /** Given a CharacterPointer range and a predicate, returns a pointer one-past the
+        last character in the range that does not satisfy the predicate.
+    */
+    template <typename Type, typename Predicate>
+    static Type trimEnd (const Type begin, Type end, Predicate&& shouldTrim)
+    {
+        while (end > begin)
+        {
+            if (! shouldTrim (--end))
+            {
+                ++end;
+                break;
+            }
+        }
+
+        return end;
+    }
+
     /** Increments a pointer until it points to the first non-whitespace character
         in a string.
 
diff --git a/modules/juce_core/text/juce_String.cpp b/modules/juce_core/text/juce_String.cpp
index d85cfd3009..cebff47d96 100644
--- a/modules/juce_core/text/juce_String.cpp
+++ b/modules/juce_core/text/juce_String.cpp
@@ -1668,64 +1668,53 @@ String String::quoted (juce_wchar quoteCharacter) const
 }
 
 //==============================================================================
-static String::CharPointerType findTrimmedEnd (const String::CharPointerType start,
-                                               String::CharPointerType end)
-{
-    while (end > start)
-    {
-        if (! (--end).isWhitespace())
-        {
-            ++end;
-            break;
-        }
-    }
-
-    return end;
-}
-
 String String::trim() const
 {
-    if (isNotEmpty())
-    {
-        auto start = text.findEndOfWhitespace();
-        auto end = start.findTerminatingNull();
-        auto trimmedEnd = findTrimmedEnd (start, end);
+    if (isEmpty())
+        return *this;
 
-        if (trimmedEnd <= start)
-            return {};
+    const auto b = begin();
+    const auto e = end();
 
-        if (text < start || trimmedEnd < end)
-            return String (start, trimmedEnd);
-    }
+    const auto shouldTrim = [] (auto ptr) { return ptr.isWhitespace(); };
+    const auto trimmedBegin = CharacterFunctions::trimBegin (b, e, shouldTrim);
+    const auto trimmedEnd = CharacterFunctions::trimEnd (trimmedBegin, e, shouldTrim);
 
-    return *this;
+    if (trimmedBegin == b && trimmedEnd == e)
+        return *this;
+
+    return String (trimmedBegin, trimmedEnd);
 }
 
 String String::trimStart() const
 {
-    if (isNotEmpty())
-    {
-        auto t = text.findEndOfWhitespace();
+    if (isEmpty())
+        return *this;
 
-        if (t != text)
-            return String (t);
-    }
+    const auto shouldTrim = [] (auto ptr) { return ptr.isWhitespace(); };
+    const auto b = begin();
+    const auto t = CharacterFunctions::trimBegin (b, end(), shouldTrim);
 
-    return *this;
+    if (t == b)
+        return *this;
+
+    return String (t);
 }
 
 String String::trimEnd() const
 {
-    if (isNotEmpty())
-    {
-        auto end = text.findTerminatingNull();
-        auto trimmedEnd = findTrimmedEnd (text, end);
+    if (isEmpty())
+        return *this;
 
-        if (trimmedEnd < end)
-            return String (text, trimmedEnd);
-    }
+    const auto shouldTrim = [] (auto ptr) { return ptr.isWhitespace(); };
+    const auto b = begin();
+    const auto e = end();
+    const auto t = CharacterFunctions::trimEnd (b, e, shouldTrim);
 
-    return *this;
+    if (t == e)
+        return *this;
+
+    return String (b, t);
 }
 
 String String::trimCharactersAtStart (StringRef charactersToTrim) const
diff --git a/modules/juce_graphics/fonts/juce_GlyphArrangement.cpp b/modules/juce_graphics/fonts/juce_GlyphArrangement.cpp
index 9178456a2e..768b72ee32 100644
--- a/modules/juce_graphics/fonts/juce_GlyphArrangement.cpp
+++ b/modules/juce_graphics/fonts/juce_GlyphArrangement.cpp
@@ -35,12 +35,26 @@
 namespace juce
 {
 
-static constexpr bool isNonBreakingSpace (const juce_wchar c)
+static String portableTrim (String toTrim)
 {
-    return c == 0x00a0
-        || c == 0x2007
-        || c == 0x202f
-        || c == 0x2060;
+    if (toTrim.isEmpty())
+        return toTrim;
+
+    const auto b = toTrim.begin();
+    const auto e = toTrim.end();
+
+    const auto shouldTrim = [] (auto ptr)
+    {
+        return SBCodepointGetBidiType ((SBCodepoint) *ptr) == SBBidiTypeWS;
+    };
+
+    const auto trimmedBegin = CharacterFunctions::trimBegin (b, e, shouldTrim);
+    const auto trimmedEnd = CharacterFunctions::trimEnd (trimmedBegin, e, shouldTrim);
+
+    if (trimmedBegin == b && trimmedEnd == e)
+        return toTrim;
+
+    return String (trimmedBegin, trimmedEnd);
 }
 
 static bool areAllRequiredWidthsSmallerThanMax (const detail::ShapedText& shapedText, float width)
@@ -268,7 +282,7 @@ static auto createFittedText (const Font& f,
         return st;
     }
 
-    const auto trimmed = text.trim();
+    const auto trimmed = portableTrim (text);
 
     constexpr auto widthFittingTolerance = 0.01f;