docs: Improvements to Text API documentation

Ref T7855
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Ref T7937
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5 files changed, 140 insertions, 117 deletions

diff --git a/src/lib/efl/interfaces/efl_text_font_properties.eo b/src/lib/efl/interfaces/efl_text_font_properties.eo
index 160b182803..71d8e3d5d9 100644
--- a/src/lib/efl/interfaces/efl_text_font_properties.eo
+++ b/src/lib/efl/interfaces/efl_text_font_properties.eo
@@ -1,50 +1,54 @@
 import efl_gfx_types;
 enum @beta Efl.Text_Font_Weight {
-   [[Type of font weight.]]
-   normal, [[Normal font weight.]]
-   thin, [[Thin font weight.]]
-   ultralight, [[Ultralight font weight.]]
-   extralight, [[Extralight font weight.]]
-   light, [[Light font weight.]]
-   book, [[Book font weight.]]
-   medium, [[Medium font weight.]]
-   semibold, [[Semibold font weight.]]
-   bold, [[Bold font weight.]]
-   ultrabold, [[Ultrabold font weight.]]
-   extrabold, [[Extrabold font weight.]]
-   black, [[Black font weight.]]
-   extrablack, [[Extrablack font weight.]]
+   [[The weight of a particular font is the thickness of the character outlines relative to their height.
+     The given numerical values follow the TrueType scale (from 100 to 900) and are approximate.
+     It is up to each font to provide all of them.]]
+   normal,     [[Normal font weight (400).]]
+   thin,       [[Thin font weight (100).]]
+   ultralight, [[Ultralight font weight (200).]]
+   extralight, [[Extralight font weight (200).]]
+   light,      [[Light font weight (300).]]
+   book,       [[Book font weight (350).]]
+   medium,     [[Medium font weight (500).]]
+   semibold,   [[Semibold font weight (600).]]
+   bold,       [[Bold font weight (700).]]
+   ultrabold,  [[Ultrabold font weight (800).]]
+   extrabold,  [[Extrabold font weight (800).]]
+   black,      [[Black font weight (900).]]
+   extrablack, [[Extrablack font weight (950).]]
 }
 
 enum @beta Efl.Text_Font_Width {
-   [[Type of font width.]]
-   normal, [[Normal font width.]]
+   [[Font width relative to its height.
+     It is up to each font to provide all these widths.]]
+   normal,         [[Normal font width.]]
    ultracondensed, [[Ultracondensed font width.]]
    extracondensed, [[Extracondensed font width.]]
-   condensed, [[Condensed font width.]]
-   semicondensed, [[Semicondensed font width.]]
-   semiexpanded, [[Semiexpanded font width.]]
-   expanded, [[Expanded font width.]]
-   extraexpanded, [[Extraexpanded font width.]]
-   ultraexpanded, [[Ultraexpanded font width.]]
+   condensed,      [[Condensed font width.]]
+   semicondensed,  [[Semicondensed font width.]]
+   semiexpanded,   [[Semiexpanded font width.]]
+   expanded,       [[Expanded font width.]]
+   extraexpanded,  [[Extraexpanded font width.]]
+   ultraexpanded,  [[Ultraexpanded font width.]]
 }
 
 enum @beta Efl.Text_Font_Slant {
     [[Type of font slant.]]
-    normal, [[Normal font slant.]]
-    oblique, [[Oblique font slant.]]
-    italic, [[Italic font slant.]]
+    normal,  [[Normal font slant: Sets the text to the normal font (non-italicized).]]
+    oblique, [[Oblique font slant: Sets the text to use a simulated version of an italic font,
+               created by algorithmically slanting the normal version.]]
+    italic,  [[Italic font slant: Sets the text to use the italic version of the font if available.
+               If not available, it will simulate italics with oblique instead.]]
 }
 
 enum @beta Efl.Text_Font_Bitmap_Scalable {
-   [[Scalable of bitmap fonts.
-   ]]
-   none = 0,         [[Disable scalable feature for bitmap fonts.]]
-   color = (1 << 0), [[Enable scalable feature for color bitmap fonts.]]
+   [[When are bitmap fonts allowed to be scaled.]]
+   none = 0,         [[Disable scaling for bitmap fonts.]]
+   color = (1 << 0), [[Enable scaling for color bitmap fonts.]]
 }
 
 interface @beta Efl.Text_Font_Properties {
-   [[Font settings for text.
+   [[Properties related to font handling.
    ]]
    c_prefix: efl_text;
    methods {
@@ -72,9 +76,9 @@ interface @beta Efl.Text_Font_Properties {
       }
 
       @property font_size {
-         [[The font size for a given text object.
+         [[The font size to use, in points.
 
-           This property controls the font size of a text object.
+           If the specified @.font_family does not provide this particular size, it will be scaled.
          ]]
          set {}
          get {}
@@ -112,7 +116,7 @@ interface @beta Efl.Text_Font_Properties {
       }
 
       @property font_weight {
-         [[Type of weight of the displayed font
+         [[Type of weight (e.g. bold or normal) of the displayed font
 
            Default is @Efl.Text_Font_Weight.normal.
          ]]
@@ -122,7 +126,7 @@ interface @beta Efl.Text_Font_Properties {
       }
 
       @property font_slant {
-         [[Type of slant of the displayed font.
+         [[Type of slant (e.g. italic or normal) of the displayed font.
 
            Default is @Efl.Text_Font_Slant.normal.
          ]]
@@ -132,7 +136,7 @@ interface @beta Efl.Text_Font_Properties {
       }
 
       @property font_width {
-         [[Type of width of the displayed font.
+         [[Type of width (e.g. condensed, expanded or normal) of the displayed font.
 
            Default is @Efl.Text_Font_Width.normal.
          ]]
@@ -155,14 +159,14 @@ interface @beta Efl.Text_Font_Properties {
       }
 
       @property font_bitmap_scalable {
-           [[The bitmap fonts have fixed size glyphs for several available sizes.
-             Basically, it is not scalable. But, it needs to be scalable for some use cases.
-             (e.g. colorful emoji fonts)
+           [[Bitmap fonts have fixed size glyphs for several available sizes.
+             Other sizes need to be algorithmically scaled, resulting in blurry glyphs.
+             This property controls whether scaling of non-provided sizes is allowed.
 
              Default is @Efl.Text_Font_Bitmap_Scalable.none.
            ]]
            values {
-              scalable: Efl.Text_Font_Bitmap_Scalable; [[Scalable.]]
+              scalable: Efl.Text_Font_Bitmap_Scalable; [[When should bitmap fonts be scaled.]]
            }
       }
    }
diff --git a/src/lib/efl/interfaces/efl_text_format.eo b/src/lib/efl/interfaces/efl_text_format.eo
index 96b724c84b..14d80a107c 100644
--- a/src/lib/efl/interfaces/efl_text_format.eo
+++ b/src/lib/efl/interfaces/efl_text_format.eo
@@ -1,5 +1,5 @@
 enum @beta Efl.Text_Format_Wrap {
-   [[Wrapping policy of the text.]]
+   [[Wrapping policy for the text.]]
    none, [[No wrapping.]]
    char, [[Wrap at character boundaries.]]
    word, [[Wrap at word boundaries.]]
@@ -9,7 +9,7 @@ enum @beta Efl.Text_Format_Wrap {
 }
 
 enum @beta Efl.Text_Format_Horizontal_Alignment_Auto_Type {
-   [[Auto-horizontal alignment setting for the text (Left-To-Right or Right-To-Left).]]
+   [[Automatic horizontal alignment setting for the text (Left-To-Right or Right-To-Left).]]
    none,   [[No auto-alignment rule: Horizontal Alignment is decided by @Efl.Text_Format.text_horizontal_align]]
    auto,   [[Respects LTR/RTL (bidirectional) characters found inside the text content.]]
    locale, [[Respects the system's language settings.]]
@@ -33,36 +33,42 @@ interface @beta Efl.Text_Format {
          ]]
          values
          {
-            value: double; [[Ellipsis value.]]
+            value: double; [[Position of the ellipsis inside the text, from $[0.0] to $[1.0].]]
          }
       }
 
       @property wrap {
-         [[Wrapping policy of the text. Requires @.multiline to be $true.]]
+         [[Wrapping policy for the text.
+
+           When text does not fit the widget in a single line, it can be automatically wrapped at
+           character or word boundaries, for example.
+
+           Requires @.multiline to be $true.
+         ]]
          values {
-            wrap: Efl.Text_Format_Wrap; [[Wrap mode.]]
+            wrap: Efl.Text_Format_Wrap; [[Wrapping policy.]]
          }
       }
 
       @property multiline {
          [[Enables text to span multiple lines.
-         
+
            When $false, new-line characters are ignored and no text wrapping occurs.
          ]]
          values {
-            enabled: bool; [[$true if multiline is enabled.]]
+            enabled: bool; [[$true if multiple lines should be rendered.]]
          }
       }
 
       @property text_horizontal_align_auto_type {
          [[Specifies when the text's horizontal alignment should be set automatically.]]
          values {
-            value: Efl.Text_Format_Horizontal_Alignment_Auto_Type; [[Alignment type.]]
+            value: Efl.Text_Format_Horizontal_Alignment_Auto_Type; [[Automatic horizontal alignment type.]]
          }
       }
 
       @property text_horizontal_align {
-         [[Horizontal alignment of text. $[0.0] means "left"
+         [[Manual horizontal alignment of text. $[0.0] means "left"
            and $[1.0] means "right".
            Setting this value also sets @.text_horizontal_align_auto_type to
            @Efl.Text_Format_Horizontal_Alignment_Auto_Type.none.
@@ -75,7 +81,7 @@ interface @beta Efl.Text_Format {
       }
 
       @property text_vertical_align {
-         [[Vertical alignment of text.$[0.0] means "top"
+         [[Vertical alignment of text. $[0.0] means "top"
            and $[1.0] means "bottom"]]
          values {
             value: double; [[Alignment value between $[0.0] and $[1.0].]]
@@ -105,16 +111,16 @@ interface @beta Efl.Text_Format {
       }
 
       @property tab_stops {
-         [[Size of the tab character.]]
+         [[Size (in pixels) of the tab character.]]
          values
          {
-            value: int; [[Size in pixels.]]
+            value: int; [[Size in pixels, greater than 1.]]
          }
       }
 
       @property password {
          [[Enabling this causes all characters to be replaced by @.replacement_char.
-         
+
            This is useful for password input boxes.
          ]]
          values
@@ -124,13 +130,12 @@ interface @beta Efl.Text_Format {
       }
 
       @property replacement_char {
-         [[The character used to replace characters that can't be displayed
+         [[The character used to replace characters that can't be displayed.
 
-           Currently only used to replace characters if @.password
-           is enabled.
+           Only used to replace characters if @.password is enabled.
          ]]
          values {
-            repch: string; [[Replacement character]]
+            repch: string; [[Replacement character.]]
          }
       }
    }
diff --git a/src/lib/efl/interfaces/efl_text_style.eo b/src/lib/efl/interfaces/efl_text_style.eo
index a975ebdc96..bb168fd5dd 100644
--- a/src/lib/efl/interfaces/efl_text_style.eo
+++ b/src/lib/efl/interfaces/efl_text_style.eo
@@ -1,70 +1,80 @@
 enum @beta Efl.Text_Style_Background_Type
 {
-   [[Whether to add a background colored rectangle (background) to each line of text or not.]]
-   none = 0, [[Do not use background.]]
-   solid_color,  [[Use solid color background.]]
-
+   [[Type of background to use behind each line of text.]]
+   none = 0,    [[Do not use background.]]
+   solid_color, [[Use a solid-color rectangle as background.
+                  Requires @Efl.Text_Style.text_background_color.]]
 }
 
 enum @beta Efl.Text_Style_Strikethrough_Type
 {
    [[Whether to add a strike-through decoration to the displayed text or not.]]
    none = 0, [[Do not use strike-through.]]
-   single,  [[Strikethrough with a single line.]]
-
+   single,   [[Strike-through with a single line.
+               Requires @Efl.Text_Style.text_strikethrough_color.]]
 }
 
 enum @beta Efl.Text_Style_Effect_Type
 {
    [[Effect to apply to the displayed text.]]
-   none = 0, [[No effect.]]
-
-   // colored with shadow_color
-   shadow, [[Shadow effect.]]
-   far_shadow, [[Far shadow effect.]]
-   soft_shadow, [[Soft shadow effect.]]
-   far_soft_shadow, [[Far and soft shadow effect.]]
-   // colored with glow_color
-   glow, [[Glow effect.]]
-   // colored with outline_color
-   outline, [[Outline effect.]]
-   soft_outline, [[Soft outline effect.]]
-   // colored with outline_color + shadow_color
-   outline_shadow, [[Outline + shadow effect.]]
-   outline_soft_shadow, [[Outline + soft shadow effect.]]
+   none = 0,            [[No effect.]]
+   shadow,              [[Shadow effect.
+                          Uses @Efl.Text_Style.text_shadow_color and @Efl.Text_Style.text_shadow_direction.]]
+   far_shadow,          [[Far shadow effect.
+                          Uses @Efl.Text_Style.text_shadow_color and @Efl.Text_Style.text_shadow_direction.]]
+   soft_shadow,         [[Soft shadow effect.
+                          Uses @Efl.Text_Style.text_shadow_color and @Efl.Text_Style.text_shadow_direction.]]
+   far_soft_shadow,     [[Far and soft shadow effect.
+                          Uses @Efl.Text_Style.text_shadow_color and @Efl.Text_Style.text_shadow_direction.]]
+   glow,                [[Glow effect.
+                          Uses @Efl.Text_Style.text_glow_color and @Efl.Text_Style.text_secondary_glow_color.]]
+   outline,             [[Outline effect.
+                          Uses @Efl.Text_Style.text_outline_color.]]
+   soft_outline,        [[Soft outline effect.
+                          Uses @Efl.Text_Style.text_outline_color.]]
+   outline_shadow,      [[Outline + shadow effect.
+                          Uses @Efl.Text_Style.text_shadow_color, @Efl.Text_Style.text_shadow_direction and
+                          @Efl.Text_Style.text_outline_color.]]
+   outline_soft_shadow, [[Outline + soft shadow effect.
+                          Uses @Efl.Text_Style.text_shadow_color, @Efl.Text_Style.text_shadow_direction and
+                          @Efl.Text_Style.text_outline_color.]]
 }
 
 enum @beta Efl.Text_Style_Shadow_Direction
 {
-   [[Direction of the shadow.]]
+   [[Direction of the shadow effect.]]
    bottom_right = 0, [[Shadow towards bottom right.]]
-   bottom, [[Shadow towards bottom.]]
-   bottom_left, [[Shadow towards bottom left.]]
-   left, [[Shadow towards left.]]
-   top_left, [[Shadow towards top left.]]
-   top, [[Shadow towards top.]]
-   top_right, [[Shadow towards top right.]]
-   right, [[Shadow towards right.]]
+   bottom,           [[Shadow towards bottom.]]
+   bottom_left,      [[Shadow towards bottom left.]]
+   left,             [[Shadow towards left.]]
+   top_left,         [[Shadow towards top left.]]
+   top,              [[Shadow towards top.]]
+   top_right,        [[Shadow towards top right.]]
+   right,            [[Shadow towards right.]]
 }
 
 enum @beta Efl.Text_Style_Underline_Type
 {
-   [[Type of underline of the displayed text.]]
+   [[Type of underline for the displayed text.]]
    none = 0, [[Text without underline.]]
-   single, [[Underlined with a single line.]]
-   double, [[Underlined with a double line.]]
-   dashed, [[Underlined with a dashed line.]]
+   single,   [[Underlined with a single line.
+               Requires @Efl.Text_Style.text_underline_color.]]
+   double,   [[Underlined with a double line.
+               Requires @Efl.Text_Style.text_underline_color and @Efl.Text_Style.text_secondary_underline_color.]]
+   dashed,   [[Underlined with a dashed line.
+               Requires @Efl.Text_Style.text_underline_dashed_color, @Efl.Text_Style.text_underline_dashed_width and
+               @Efl.Text_Style.text_underline_dashed_gap.]]
 }
 
 interface @beta Efl.Text_Style {
    [[Decorations to add to the text.
 
-     Decorations can be coloring, effects, underlines, strike-through etc.
+     Decorations include text color, glow, outline, underline, strike-through and shadows.
    ]]
    c_prefix: efl_text;
    methods {
       @property text_color {
-         [[Color of text, excluding decorations like, shadow, outline or glow.]]
+         [[Color of text, excluding all other decorations. By default it is invisible.]]
          values
          {
             r: ubyte; [[Red component.]]
@@ -75,7 +85,7 @@ interface @beta Efl.Text_Style {
       }
 
       @property text_background_type {
-         [[Enables rendering of a background rectangle behind each line of text.]]
+         [[Type of background to use behind each line of text.]]
          values
          {
             type: Efl.Text_Style_Background_Type; [[Background type.]]
@@ -83,7 +93,7 @@ interface @beta Efl.Text_Style {
       }
 
       @property text_background_color {
-          [[Color of the background rectangle (backing) behind each line of text.]]
+         [[Color of the background behind each line of text. By default it is invisible.]]
          values
          {
             r: ubyte; [[Red component.]]
@@ -94,7 +104,7 @@ interface @beta Efl.Text_Style {
       }
 
       @property text_underline_type {
-         [[Underline style for the text.]]
+         [[Type of underline to use for the text.]]
          values
          {
             type: Efl.Text_Style_Underline_Type; [[Underline type.]]
@@ -103,7 +113,7 @@ interface @beta Efl.Text_Style {
 
       @property text_underline_color
       {
-         [[Color of normal underline style.]]
+         [[Color of the primary underline. By default it is invisible.]]
          values
          {
             r: ubyte; [[Red component.]]
@@ -126,7 +136,7 @@ interface @beta Efl.Text_Style {
       @property text_underline_dashed_color
       {
          [[Color of the dashed underline. Only valid when @.text_underline_type is
-           @Efl.Text_Style_Underline_Type.dashed.]]
+           @Efl.Text_Style_Underline_Type.dashed. By default it is invisible.]]
          values
          {
             r: ubyte; [[Red component.]]
@@ -159,7 +169,7 @@ interface @beta Efl.Text_Style {
       @property text_secondary_underline_color
       {
          [[Color of the secondary underline. Only valid when @.text_underline_type is
-           @Efl.Text_Style_Underline_Type.double.]]
+           @Efl.Text_Style_Underline_Type.double. By default it is invisible.]]
          values
          {
             r: ubyte; [[Red component.]]
@@ -179,7 +189,7 @@ interface @beta Efl.Text_Style {
 
       @property text_strikethrough_color
       {
-         [[Color of the line striking through the text.]]
+         [[Color of the line striking through the text. By default it is invisible.]]
          values
          {
             r: ubyte; [[Red component.]]
@@ -198,7 +208,7 @@ interface @beta Efl.Text_Style {
       }
       @property text_outline_color
       {
-         [[Color of the text outline.]]
+         [[Color of the text outline. By default it is invisible.]]
          values
          {
             r: ubyte; [[Red component.]]
@@ -210,7 +220,7 @@ interface @beta Efl.Text_Style {
 
       @property text_shadow_direction
       {
-         [[Direction of shadow effect.]]
+         [[Direction of the shadow effect.]]
          values
          {
             type: Efl.Text_Style_Shadow_Direction; [[Shadow direction.]]
@@ -219,7 +229,7 @@ interface @beta Efl.Text_Style {
 
       @property text_shadow_color
       {
-         [[Color of the shadow.]]
+         [[Color of the text shadow. By default it is invisible.]]
          values
          {
             r: ubyte; [[Red component.]]
@@ -231,7 +241,7 @@ interface @beta Efl.Text_Style {
 
       @property text_glow_color
       {
-         [[Color of the glow decoration.]]
+         [[Color of the text glow. By default it is invisible.]]
          values
          {
             r: ubyte; [[Red component.]]
@@ -245,7 +255,8 @@ interface @beta Efl.Text_Style {
       {
          [[Color of the secondary glow decoration.
            This is the color of the inner glow (where it touches the text) which
-           gradually fades into @.text_glow_color as it reaches the edge.
+           gradually fades into @.text_glow_color as it reaches the outer edge.
+           By default it is invisible.
          ]]
          values
          {
@@ -264,7 +275,7 @@ interface @beta Efl.Text_Style {
          ]]
          values
          {
-            code: string; [[Filter code]]
+            code: string; [[Filter code.]]
          }
       }
    }
diff --git a/src/lib/elementary/efl_ui_textbox.eo b/src/lib/elementary/efl_ui_textbox.eo
index aa3a5dd5be..ce4ca09b24 100644
--- a/src/lib/elementary/efl_ui_textbox.eo
+++ b/src/lib/elementary/efl_ui_textbox.eo
@@ -6,7 +6,7 @@ class @beta Efl.Ui.Textbox extends Efl.Ui.Layout_Base implements Efl.Input.Click
    [[A flexible text widget which can be static (as a label) or editable by
      the user (as a text entry). It provides all sorts of editing facilities
      like automatic scrollbars, virtual keyboard, clipboard, configurable
-     context menus or autocapitalization, for example.]]
+     context menus or auto-capitalization, for example.]]
    methods {
       @property scrollable {
          [[Enable or disable scrolling in the widget.
@@ -16,17 +16,19 @@ class @beta Efl.Ui.Textbox extends Efl.Ui.Layout_Base implements Efl.Input.Click
          set {}
          get {}
          values {
-            scroll: bool; [[$true to enable scrolling. Default is $false.]]
+            scroll: bool(false); [[$true to enable scrolling.]]
          }
       }
       @property context_menu_enabled {
-         [[This enables or disables the entry's contextual (longpress) menu.]]
+         [[This enables or disables the widget's contextual menu, typically
+           accessible through a long-press or a right-button click.
+         ]]
          set {
          }
          get {
          }
          values {
-            enabled: bool; [[If $true, the menu is enabled.]]
+            enabled: bool; [[$true to enable the contextual menu.]]
          }
       }
       @property cnp_mode {
@@ -46,13 +48,14 @@ class @beta Efl.Ui.Textbox extends Efl.Ui.Layout_Base implements Efl.Input.Click
          }
       }
       @property selection_handles_enabled {
-         [[This enables or disables the entry's selection handlers.]]
+         [[This enables or disables the visual handles around selected text,
+           to allow simpler modification on touch screens.]]
          set {
          }
          get {
          }
          values {
-            enabled: bool; [[If $true, the selection handlers are enabled.]]
+            enabled: bool; [[$true to enable the selection handles.]]
          }
       }
 
@@ -69,13 +72,13 @@ class @beta Efl.Ui.Textbox extends Efl.Ui.Layout_Base implements Efl.Input.Click
          return: Efl.Text.Cursor @move; [[Text cursor.]]
       }
       selection_copy {
-         [[This executes a "copy" action on the selected text in the entry.]]
+         [[This executes a "copy" action on the selected text in the widget.]]
       }
       selection_paste {
-         [[This executes a "paste" action in the entry.]]
+         [[This executes a "paste" action in the widget.]]
       }
       selection_cut {
-         [[This executes a "cut" action on the selected text in the entry.]]
+         [[This executes a "cut" action on the selected text in the widget.]]
       }
    }
    implements {
diff --git a/src/lib/evas/canvas/efl_canvas_textblock.eo b/src/lib/evas/canvas/efl_canvas_textblock.eo
index edc170ba81..8e9bee7dba 100644
--- a/src/lib/evas/canvas/efl_canvas_textblock.eo
+++ b/src/lib/evas/canvas/efl_canvas_textblock.eo
@@ -140,8 +140,8 @@ class @beta Efl.Canvas.Textblock extends Efl.Canvas.Object implements Efl.Text,
              Requires $underline.
              See @Efl.Text_Style.text_underline_color.
 
-           - $secondary_underline_color: Color code for the secondary text underline (See bottom for the complete list of
-             supported codes). Only valid when $[underline=double].
+           - $secondary_underline_color: Color code for the secondary text underline (See bottom for the complete list
+             of supported codes). Only valid when $[underline=double].
              Default value is $[rgba(0,0,0,0)] meaning that secondary underline will not be rendered.
              See @Efl.Text_Style.text_secondary_underline_color.
 
@@ -165,8 +165,8 @@ class @beta Efl.Canvas.Textblock extends Efl.Canvas.Object implements Efl.Text,
              Default value is $[rgba(0,0,0,0)] meaning that no glow will be rendered.
              See @Efl.Text_Style.text_glow_color.
 
-           - $secondary_glow_color: Color code for the secondary (inner) glow component of the text (See bottom for the complete
-             list of supported codes). Only valid when the $style attribute includes a glow.
+           - $secondary_glow_color: Color code for the secondary (inner) glow component of the text (See bottom for
+             the complete list of supported codes). Only valid when the $style attribute includes a glow.
              Default value is $[rgba(0,0,0,0)] meaning that only the primary $glow_color will be used.
              See @Efl.Text_Style.text_secondary_glow_color.