--- a/devtools/shared/css/generated/properties-db.js
+++ b/devtools/shared/css/generated/properties-db.js
@@ -3040,16 +3040,17 @@ exports.CSS_PROPERTIES = {
       "text-decoration-color",
       "text-decoration-line",
       "text-decoration-style",
       "text-emphasis-color",
       "text-emphasis-position",
       "text-emphasis-style",
       "-webkit-text-fill-color",
       "text-indent",
+      "text-justify",
       "text-orientation",
       "text-overflow",
       "text-rendering",
       "text-shadow",
       "-moz-text-size-adjust",
       "-webkit-text-stroke-color",
       "-webkit-text-stroke-width",
       "text-transform",
@@ -9482,16 +9483,20 @@ exports.PREFERENCES = [
     "text-combine-upright",
     "layout.css.text-combine-upright.enabled"
   ],
   [
     "-webkit-text-fill-color",
     "layout.css.prefixes.webkit"
   ],
   [
+    "text-justify",
+    "layout.css.text-justify.enabled"
+  ],
+  [
     "-webkit-text-stroke",
     "layout.css.prefixes.webkit"
   ],
   [
     "-webkit-text-stroke-color",
     "layout.css.prefixes.webkit"
   ],
   [

--- a/dom/ipc/ContentPrefs.cpp
+++ b/dom/ipc/ContentPrefs.cpp
@@ -136,16 +136,17 @@ const char* mozilla::dom::ContentPrefs::
   "layout.css.scope-pseudo.enabled",
   "layout.css.scroll-behavior.property-enabled",
   "layout.css.scroll-snap.enabled",
   "layout.css.servo.enabled",
   "layout.css.shape-outside.enabled",
   "layout.css.text-align-unsafe-value.enabled",
   "layout.css.text-combine-upright-digits.enabled",
   "layout.css.text-combine-upright.enabled",
+  "layout.css.text-justify.enabled",
   "layout.css.touch_action.enabled",
   "layout.css.unprefixing-service.enabled",
   "layout.css.unprefixing-service.globally-whitelisted",
   "layout.css.unprefixing-service.include-test-domains",
   "layout.css.variables.enabled",
   "layout.css.visited_links_enabled",
   "layout.idle_period.required_quiescent_frames",
   "layout.idle_period.time_limit",

--- a/layout/style/nsCSSKeywordList.h
+++ b/layout/style/nsCSSKeywordList.h
@@ -230,16 +230,17 @@ CSS_KEY(diagonal-fractions, diagonal_fra
 CSS_KEY(dialog, dialog)
 CSS_KEY(difference, difference)
 CSS_KEY(digits, digits)
 CSS_KEY(disabled, disabled)
 CSS_KEY(disc, disc)
 CSS_KEY(disclosure-closed, disclosure_closed)
 CSS_KEY(disclosure-open, disclosure_open)
 CSS_KEY(discretionary-ligatures, discretionary_ligatures)
+CSS_KEY(distribute, distribute)
 CSS_KEY(dot, dot)
 CSS_KEY(dotted, dotted)
 CSS_KEY(double, double)
 CSS_KEY(double-circle, double_circle)
 CSS_KEY(double-struck, double_struck)
 CSS_KEY(drag, drag)
 CSS_KEY(drop-shadow, drop_shadow)
 CSS_KEY(e-resize, e_resize)
@@ -326,17 +327,18 @@ CSS_KEY(inline-axis, inline_axis)
 CSS_KEY(inline-block, inline_block)
 CSS_KEY(inline-end, inline_end)
 CSS_KEY(inline-flex, inline_flex)
 CSS_KEY(inline-grid, inline_grid)
 CSS_KEY(inline-start, inline_start)
 CSS_KEY(inline-table, inline_table)
 CSS_KEY(inset, inset)
 CSS_KEY(inside, inside)
-// CSS_KEY(inter-character, inter_character) // TODO see bug 1055672
+CSS_KEY(inter-character, inter_character)
+CSS_KEY(inter-word, inter_word)
 CSS_KEY(interpolatematrix, interpolatematrix)
 CSS_KEY(accumulatematrix, accumulatematrix)
 CSS_KEY(intersect, intersect)
 CSS_KEY(isolate, isolate)
 CSS_KEY(isolate-override, isolate_override)
 CSS_KEY(invert, invert)
 CSS_KEY(italic, italic)
 CSS_KEY(japanese-formal, japanese_formal)

--- a/layout/style/nsCSSPropList.h
+++ b/layout/style/nsCSSPropList.h
@@ -4047,16 +4047,27 @@ CSS_PROP_TEXT(
     CSS_PROPERTY_PARSE_VALUE |
         CSS_PROPERTY_STORES_CALC |
         CSS_PROPERTY_UNITLESS_LENGTH_QUIRK,
     "",
     VARIANT_HLP | VARIANT_CALC,
     nullptr,
     offsetof(nsStyleText, mTextIndent),
     eStyleAnimType_Coord)
+CSS_PROP_TEXT(
+    text-justify,
+    text_justify,
+    TextJustify,
+    CSS_PROPERTY_PARSE_VALUE |
+        CSS_PROPERTY_APPLIES_TO_PLACEHOLDER,
+    "layout.css.text-justify.enabled",
+    VARIANT_HK,
+    kTextJustifyKTable,
+    CSS_PROP_NO_OFFSET,
+    eStyleAnimType_Discrete)
 CSS_PROP_VISIBILITY(
     text-orientation,
     text_orientation,
     TextOrientation,
     CSS_PROPERTY_PARSE_VALUE,
     "",
     VARIANT_HK,
     kTextOrientationKTable,

--- a/layout/style/nsCSSProps.cpp
+++ b/layout/style/nsCSSProps.cpp
@@ -1995,16 +1995,27 @@ KTableEntry nsCSSProps::kTextAlignLastKT
   { eCSSKeyword_center, NS_STYLE_TEXT_ALIGN_CENTER },
   { eCSSKeyword_justify, NS_STYLE_TEXT_ALIGN_JUSTIFY },
   { eCSSKeyword_start, NS_STYLE_TEXT_ALIGN_START },
   { eCSSKeyword_end, NS_STYLE_TEXT_ALIGN_END },
   { eCSSKeyword_unsafe, NS_STYLE_TEXT_ALIGN_UNSAFE },
   { eCSSKeyword_UNKNOWN, -1 }
 };
 
+const KTableEntry nsCSSProps::kTextJustifyKTable[] = {
+  { eCSSKeyword_none, StyleTextJustify::None },
+  { eCSSKeyword_auto, StyleTextJustify::Auto },
+  { eCSSKeyword_inter_word, StyleTextJustify::InterWord },
+  { eCSSKeyword_inter_character, StyleTextJustify::InterCharacter },
+  // For legacy reasons, UAs must also support the keyword "distribute" with
+  // the exact same meaning and behavior as "inter-character".
+  { eCSSKeyword_distribute, StyleTextJustify::InterCharacter },
+  { eCSSKeyword_UNKNOWN, -1 }
+};
+
 const KTableEntry nsCSSProps::kTextCombineUprightKTable[] = {
   { eCSSKeyword_none, NS_STYLE_TEXT_COMBINE_UPRIGHT_NONE },
   { eCSSKeyword_all, NS_STYLE_TEXT_COMBINE_UPRIGHT_ALL },
   { eCSSKeyword_digits, NS_STYLE_TEXT_COMBINE_UPRIGHT_DIGITS_2 }, // w/o number ==> 2
   { eCSSKeyword_UNKNOWN, -1 }
 };
 
 const KTableEntry nsCSSProps::kTextDecorationLineKTable[] = {

--- a/layout/style/nsCSSProps.h
+++ b/layout/style/nsCSSProps.h
@@ -842,16 +842,17 @@ public:
   static KTableEntry kTextAlignKTable[];
   static KTableEntry kTextAlignLastKTable[];
   static const KTableEntry kTextCombineUprightKTable[];
   static const KTableEntry kTextDecorationLineKTable[];
   static const KTableEntry kTextDecorationStyleKTable[];
   static const KTableEntry kTextEmphasisPositionKTable[];
   static const KTableEntry kTextEmphasisStyleFillKTable[];
   static const KTableEntry kTextEmphasisStyleShapeKTable[];
+  static const KTableEntry kTextJustifyKTable[];
   static const KTableEntry kTextOrientationKTable[];
   static const KTableEntry kTextOverflowKTable[];
   static const KTableEntry kTextSizeAdjustKTable[];
   static const KTableEntry kTextTransformKTable[];
   static const KTableEntry kTouchActionKTable[];
   static const KTableEntry kTopLayerKTable[];
   static const KTableEntry kTransformBoxKTable[];
   static const KTableEntry kTransitionTimingFunctionKTable[];

--- a/layout/style/nsComputedDOMStyle.cpp
+++ b/layout/style/nsComputedDOMStyle.cpp
@@ -4045,16 +4045,26 @@ already_AddRefed<CSSValue>
 nsComputedDOMStyle::DoGetTextIndent()
 {
   RefPtr<nsROCSSPrimitiveValue> val = new nsROCSSPrimitiveValue;
   SetValueToCoord(val, StyleText()->mTextIndent, false);
   return val.forget();
 }
 
 already_AddRefed<CSSValue>
+nsComputedDOMStyle::DoGetTextJustify()
+{
+  RefPtr<nsROCSSPrimitiveValue> val = new nsROCSSPrimitiveValue;
+  val->SetIdent(
+    nsCSSProps::ValueToKeywordEnum(StyleText()->mTextJustify,
+                                   nsCSSProps::kTextJustifyKTable));
+  return val.forget();
+}
+
+already_AddRefed<CSSValue>
 nsComputedDOMStyle::DoGetTextOrientation()
 {
   RefPtr<nsROCSSPrimitiveValue> val = new nsROCSSPrimitiveValue;
   val->SetIdent(
     nsCSSProps::ValueToKeywordEnum(StyleVisibility()->mTextOrientation,
                                    nsCSSProps::kTextOrientationKTable));
   return val.forget();
 }

--- a/layout/style/nsComputedDOMStyle.h
+++ b/layout/style/nsComputedDOMStyle.h
@@ -429,16 +429,17 @@ private:
   already_AddRefed<CSSValue> DoGetTextDecoration();
   already_AddRefed<CSSValue> DoGetTextDecorationColor();
   already_AddRefed<CSSValue> DoGetTextDecorationLine();
   already_AddRefed<CSSValue> DoGetTextDecorationStyle();
   already_AddRefed<CSSValue> DoGetTextEmphasisColor();
   already_AddRefed<CSSValue> DoGetTextEmphasisPosition();
   already_AddRefed<CSSValue> DoGetTextEmphasisStyle();
   already_AddRefed<CSSValue> DoGetTextIndent();
+  already_AddRefed<CSSValue> DoGetTextJustify();
   already_AddRefed<CSSValue> DoGetTextOrientation();
   already_AddRefed<CSSValue> DoGetTextOverflow();
   already_AddRefed<CSSValue> DoGetTextShadow();
   already_AddRefed<CSSValue> DoGetTextSizeAdjust();
   already_AddRefed<CSSValue> DoGetTextTransform();
   already_AddRefed<CSSValue> DoGetLetterSpacing();
   already_AddRefed<CSSValue> DoGetWordSpacing();
   already_AddRefed<CSSValue> DoGetWhiteSpace();

--- a/layout/style/nsComputedDOMStylePropertyList.h
+++ b/layout/style/nsComputedDOMStylePropertyList.h
@@ -236,16 +236,17 @@ COMPUTED_STYLE_PROP(text_decoration,    
 COMPUTED_STYLE_PROP(text_decoration_color,         TextDecorationColor)
 COMPUTED_STYLE_PROP(text_decoration_line,          TextDecorationLine)
 COMPUTED_STYLE_PROP(text_decoration_style,         TextDecorationStyle)
 //// COMPUTED_STYLE_PROP(text_emphasis,            TextEmphasis)
 COMPUTED_STYLE_PROP(text_emphasis_color,           TextEmphasisColor)
 COMPUTED_STYLE_PROP(text_emphasis_position,        TextEmphasisPosition)
 COMPUTED_STYLE_PROP(text_emphasis_style,           TextEmphasisStyle)
 COMPUTED_STYLE_PROP(text_indent,                   TextIndent)
+COMPUTED_STYLE_PROP(text_justify,                  TextJustify)
 COMPUTED_STYLE_PROP(text_orientation,              TextOrientation)
 COMPUTED_STYLE_PROP(text_overflow,                 TextOverflow)
 COMPUTED_STYLE_PROP(text_shadow,                   TextShadow)
 COMPUTED_STYLE_PROP(text_transform,                TextTransform)
 COMPUTED_STYLE_PROP(top,                           Top)
 COMPUTED_STYLE_PROP(touch_action,                  TouchAction)
 COMPUTED_STYLE_PROP(transform,                     Transform)
 COMPUTED_STYLE_PROP(transform_box,                 TransformBox)

--- a/layout/style/nsRuleNode.cpp
+++ b/layout/style/nsRuleNode.cpp
@@ -1444,16 +1444,17 @@ struct SetEnumValueHelper
   DEFINE_ENUM_CLASS_SETTER(StyleBoxOrient, Horizontal, Vertical)
   DEFINE_ENUM_CLASS_SETTER(StyleBoxPack, Start, Justify)
   DEFINE_ENUM_CLASS_SETTER(StyleBoxSizing, Content, Border)
   DEFINE_ENUM_CLASS_SETTER(StyleClear, None, Both)
   DEFINE_ENUM_CLASS_SETTER(StyleFillRule, Nonzero, Evenodd)
   DEFINE_ENUM_CLASS_SETTER(StyleFloat, None, InlineEnd)
   DEFINE_ENUM_CLASS_SETTER(StyleFloatEdge, ContentBox, MarginBox)
   DEFINE_ENUM_CLASS_SETTER(StyleHyphens, None, Auto)
+  DEFINE_ENUM_CLASS_SETTER(StyleTextJustify, None, InterCharacter)
   DEFINE_ENUM_CLASS_SETTER(StyleUserFocus, None, SelectMenu)
   DEFINE_ENUM_CLASS_SETTER(StyleUserSelect, None, MozText)
   DEFINE_ENUM_CLASS_SETTER(StyleUserInput, None, Auto)
   DEFINE_ENUM_CLASS_SETTER(StyleUserModify, ReadOnly, WriteOnly)
   DEFINE_ENUM_CLASS_SETTER(StyleWindowDragging, Default, NoDrag)
   DEFINE_ENUM_CLASS_SETTER(StyleOrient, Inline, Vertical)
 #ifdef MOZ_XUL
   DEFINE_ENUM_CLASS_SETTER(StyleDisplay, None, MozPopup)
@@ -4871,16 +4872,22 @@ nsRuleNode::ComputeTextData(void* aStart
            NS_STYLE_TEXT_ALIGN_AUTO);
 
   // text-indent: length, percent, calc, inherit, initial
   SetCoord(*aRuleData->ValueForTextIndent(), text->mTextIndent, parentText->mTextIndent,
            SETCOORD_LPH | SETCOORD_INITIAL_ZERO | SETCOORD_STORE_CALC |
              SETCOORD_UNSET_INHERIT,
            aContext, mPresContext, conditions);
 
+  // text-justify: enum, inherit, initial
+  SetValue(*aRuleData->ValueForTextJustify(), text->mTextJustify, conditions,
+           SETVAL_ENUMERATED | SETVAL_UNSET_INHERIT,
+           parentText->mTextJustify,
+           StyleTextJustify::Auto);
+
   // text-transform: enum, inherit, initial
   SetValue(*aRuleData->ValueForTextTransform(), text->mTextTransform, conditions,
            SETVAL_ENUMERATED | SETVAL_UNSET_INHERIT,
            parentText->mTextTransform,
            NS_STYLE_TEXT_TRANSFORM_NONE);
 
   // white-space: enum, inherit, initial
   SetValue(*aRuleData->ValueForWhiteSpace(), text->mWhiteSpace, conditions,

--- a/layout/style/nsStyleConsts.h
+++ b/layout/style/nsStyleConsts.h
@@ -153,16 +153,24 @@ enum class StyleShapeRadius : uint8_t {
 // Shape source type
 enum class StyleShapeSourceType : uint8_t {
   None,
   URL,
   Shape,
   Box,
 };
 
+// text-justify
+enum class StyleTextJustify : uint8_t {
+  None,
+  Auto,
+  InterWord,
+  InterCharacter,
+};
+
 // user-focus
 enum class StyleUserFocus : uint8_t {
   None,
   Ignore,
   Normal,
   SelectAll,
   SelectBefore,
   SelectAfter,

--- a/layout/style/nsStyleStruct.cpp
+++ b/layout/style/nsStyleStruct.cpp
@@ -3841,16 +3841,17 @@ AreShadowArraysEqual(nsCSSShadowArray* l
 // nsStyleText
 //
 
 nsStyleText::nsStyleText(const nsPresContext* aContext)
   : mTextAlign(NS_STYLE_TEXT_ALIGN_START)
   , mTextAlignLast(NS_STYLE_TEXT_ALIGN_AUTO)
   , mTextAlignTrue(false)
   , mTextAlignLastTrue(false)
+  , mTextJustify(StyleTextJustify::Auto)
   , mTextTransform(NS_STYLE_TEXT_TRANSFORM_NONE)
   , mWhiteSpace(NS_STYLE_WHITESPACE_NORMAL)
   , mWordBreak(NS_STYLE_WORDBREAK_NORMAL)
   , mOverflowWrap(NS_STYLE_OVERFLOWWRAP_NORMAL)
   , mHyphens(StyleHyphens::Manual)
   , mRubyAlign(NS_STYLE_RUBY_ALIGN_SPACE_AROUND)
   , mRubyPosition(NS_STYLE_RUBY_POSITION_OVER)
   , mTextSizeAdjust(NS_STYLE_TEXT_SIZE_ADJUST_AUTO)
@@ -3877,16 +3878,17 @@ nsStyleText::nsStyleText(const nsPresCon
     NS_STYLE_TEXT_EMPHASIS_POSITION_DEFAULT;
 }
 
 nsStyleText::nsStyleText(const nsStyleText& aSource)
   : mTextAlign(aSource.mTextAlign)
   , mTextAlignLast(aSource.mTextAlignLast)
   , mTextAlignTrue(false)
   , mTextAlignLastTrue(false)
+  , mTextJustify(aSource.mTextJustify)
   , mTextTransform(aSource.mTextTransform)
   , mWhiteSpace(aSource.mWhiteSpace)
   , mWordBreak(aSource.mWordBreak)
   , mOverflowWrap(aSource.mOverflowWrap)
   , mHyphens(aSource.mHyphens)
   , mRubyAlign(aSource.mRubyAlign)
   , mRubyPosition(aSource.mRubyPosition)
   , mTextSizeAdjust(aSource.mTextSizeAdjust)
@@ -3939,16 +3941,17 @@ nsStyleText::CalcDifference(const nsStyl
       (mOverflowWrap != aNewData.mOverflowWrap) ||
       (mHyphens != aNewData.mHyphens) ||
       (mRubyAlign != aNewData.mRubyAlign) ||
       (mRubyPosition != aNewData.mRubyPosition) ||
       (mTextSizeAdjust != aNewData.mTextSizeAdjust) ||
       (mLetterSpacing != aNewData.mLetterSpacing) ||
       (mLineHeight != aNewData.mLineHeight) ||
       (mTextIndent != aNewData.mTextIndent) ||
+      (mTextJustify != aNewData.mTextJustify) ||
       (mWordSpacing != aNewData.mWordSpacing) ||
       (mTabSize != aNewData.mTabSize)) {
     return NS_STYLE_HINT_REFLOW;
   }
 
   if (HasTextEmphasis() != aNewData.HasTextEmphasis() ||
       (HasTextEmphasis() &&
        mTextEmphasisPosition != aNewData.mTextEmphasisPosition)) {

--- a/layout/style/nsStyleStruct.h
+++ b/layout/style/nsStyleStruct.h
@@ -2097,16 +2097,17 @@ struct MOZ_NEEDS_MEMMOVABLE_MEMBERS nsSt
            nsChangeHint_ReflowChangesSizeOrPosition |
            nsChangeHint_ClearAncestorIntrinsics;
   }
 
   uint8_t mTextAlign;                   // [inherited] see nsStyleConsts.h
   uint8_t mTextAlignLast;               // [inherited] see nsStyleConsts.h
   bool mTextAlignTrue : 1;              // [inherited] see nsStyleConsts.h
   bool mTextAlignLastTrue : 1;          // [inherited] see nsStyleConsts.h
+  mozilla::StyleTextJustify mTextJustify;   // [inherited]
   uint8_t mTextTransform;               // [inherited] see nsStyleConsts.h
   uint8_t mWhiteSpace;                  // [inherited] see nsStyleConsts.h
   uint8_t mWordBreak;                   // [inherited] see nsStyleConsts.h
   uint8_t mOverflowWrap;                // [inherited] see nsStyleConsts.h
   mozilla::StyleHyphens mHyphens;       // [inherited] see nsStyleConsts.h
   uint8_t mRubyAlign;                   // [inherited] see nsStyleConsts.h
   uint8_t mRubyPosition;                // [inherited] see nsStyleConsts.h
   uint8_t mTextSizeAdjust;              // [inherited] see nsStyleConsts.h

--- a/layout/style/test/property_database.js
+++ b/layout/style/test/property_database.js
@@ -5565,16 +5565,27 @@ if (IsCSSPropertyPrefEnabled("layout.css
                       "digits 3 all", "digits foo", "digits all", "digits 3.0" ]
   };
   if (IsCSSPropertyPrefEnabled("layout.css.text-combine-upright-digits.enabled")) {
     gCSSProperties["text-combine-upright"].other_values.push(
       "digits", "digits 2", "digits 3", "digits 4", "digits     3");
   }
 }
 
+if (IsCSSPropertyPrefEnabled("layout.css.text-justify.enabled")) {
+  gCSSProperties["text-justify"] = {
+    domProp: "textJustify",
+    inherited: true,
+    type: CSS_TYPE_LONGHAND,
+    initial_values: [ "auto" ],
+    other_values: [ "none", "inter-word", "inter-character", "distribute" ],
+    invalid_values: []
+  };
+}
+
 if (IsCSSPropertyPrefEnabled("layout.css.font-variations.enabled")) {
   gCSSProperties["font-variation-settings"] = {
     domProp: "fontVariationSettings",
     inherited: true,
     type: CSS_TYPE_LONGHAND,
     initial_values: [ "normal" ],
     other_values: [
       "'wdth' 0", "'wdth' -.1", "\"wdth\" 1", "'wdth' 2, 'wght' 3", "\"XXXX\" 0"

--- a/modules/libpref/init/all.js
+++ b/modules/libpref/init/all.js
@@ -2571,16 +2571,19 @@ pref("layout.css.getBoxQuads.enabled", t
 pref("layout.css.convertFromNode.enabled", false);
 #else
 pref("layout.css.convertFromNode.enabled", true);
 #endif
 
 // Is support for CSS "text-align: unsafe X" enabled?
 pref("layout.css.text-align-unsafe-value.enabled", false);
 
+// Is support for CSS text-justify property enabled?
+pref("layout.css.text-justify.enabled", false);
+
 // Is support for CSS "float: inline-{start,end}" and
 // "clear: inline-{start,end}" enabled?
 #if defined(MOZ_B2G) || !defined(RELEASE_OR_BETA)
 pref("layout.css.float-logical-values.enabled", true);
 #else
 pref("layout.css.float-logical-values.enabled", false);
 #endif
 

--- a/testing/profiles/prefs_general.js
+++ b/testing/profiles/prefs_general.js
@@ -183,16 +183,19 @@ user_pref("layout.css.object-fit-and-pos
 user_pref("layout.css.prefixes.webkit", true);
 
 // Enable -webkit-{min|max}-device-pixel-ratio media queries for testing
 user_pref("layout.css.prefixes.device-pixel-ratio-webkit", true);
 
 // Enable CSS shape-outside for testing
 user_pref("layout.css.shape-outside.enabled", true);
 
+// Enable CSS text-justify for testing
+user_pref("layout.css.text-justify.enabled", true);
+
 // Disable spammy layout warnings because they pollute test logs
 user_pref("layout.spammy_warnings.enabled", false);
 
 // Enable Media Source Extensions for testing
 user_pref("media.mediasource.mp4.enabled", true);
 user_pref("media.mediasource.webm.enabled", true);
 
 // Make sure the disk cache doesn't get auto disabled