diff --git a/frontend/ui/data/koptoptions.lua b/frontend/ui/data/koptoptions.lua
index a37687a81..8385f4029 100644
--- a/frontend/ui/data/koptoptions.lua
+++ b/frontend/ui/data/koptoptions.lua
@@ -644,25 +644,28 @@ You might need to set it to 1 column if, in a full width document, text is incor
 }
 
 if BD.mirroredUILayout() then
-    -- The justification items {AUTO, LEFT, CENTER, RIGHT, JUSTIFY} will
-    -- be mirrored - but that's not enough: we need to swap LEFT and RIGHT,
-    -- so they appear in a more expected and balanced order to RTL users:
-    -- {JUSTIFY, LEFT, CENTER, RIGHT, AUTO}
-    local j = KoptOptions[4].options[5]
-    assert(j.name == "justification")
-    j.item_icons[2], j.item_icons[4] = j.item_icons[4], j.item_icons[2]
-    j.values[2], j.values[4] = j.values[4], j.values[2]
-    j.labels[2], j.labels[4] = j.labels[4], j.labels[2]
-    -- The zoom direction items will be mirrored, but we want them to
-    -- stay as is, as the RTL directions are at the end of the arrays.
-    -- By reverting the mirroring, RTL directions will be on the right,
-    -- so, at the start of the options for a RTL reader.
-    j = KoptOptions[3].options[7]
-    assert(j.name == "zoom_direction")
-    util.arrayReverse(j.item_icons)
-    util.arrayReverse(j.values)
-    util.arrayReverse(j.args)
-    j.default_value = 0
+    for _, tab in ipairs(KoptOptions) do
+        for _, option in ipairs(tab.options) do
+            if option.name == "zoom_direction" then
+                -- The zoom direction items will be mirrored, but we want them to
+                -- stay as is, as the RTL directions are at the end of the arrays.
+                -- By reverting the mirroring, RTL directions will be on the right,
+                -- so, at the start of the options for a RTL reader.
+                util.arrayReverse(option.item_icons)
+                util.arrayReverse(option.values)
+                util.arrayReverse(option.args)
+                option.default_value = 0
+            elseif option.name == "justification" then
+                -- The justification items {AUTO, LEFT, CENTER, RIGHT, JUSTIFY} will
+                -- be mirrored - but that's not enough: we need to swap LEFT and RIGHT,
+                -- so they appear in a more expected and balanced order to RTL users:
+                -- {JUSTIFY, LEFT, CENTER, RIGHT, AUTO}
+                option.item_icons[2], option.item_icons[4] = option.item_icons[4], option.item_icons[2]
+                option.values[2], option.values[4] = option.values[4], option.values[2]
+                option.labels[2], option.labels[4] = option.labels[4], option.labels[2]
+            end
+        end
+    end
 end
 
 return KoptOptions