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+# Audit: Unused DG.* Strings in `lang/strings/en-US.json`
+
+**Date:** 2026-02-14
+**Branch:** master
+**Context:** CODAP-1112 (string ownership model for V2/V3 shared POEditor project)
+
+## Methodology
+
+1. Extracted all 1,144 `DG.*` keys from `lang/strings/en-US.json`
+2. Extracted all `DG.*` string literals from `.js` files under `apps/dg/` (excluding `*.lproj/` locale files)
+3. Identified dynamic key construction patterns (15 prefix patterns like `"DG.Undo.map." + op`)
+4. A key is "used" if: (a) it appears as a full string literal in non-locale JS, or (b) it starts with a known dynamic prefix
+5. Excluded `DG.plugin.*` keys (used by separate plugin repos, not the main CODAP app)
+6. Manually verified each candidate group for missed dynamic construction
+
+## Results Summary
+
+- **Total DG.\* keys:** 1,144
+- **Used (direct or dynamic prefix):** 832
+- **DG.plugin.\* keys (used by plugins):** 212
+- **Confirmed unused:** ~85 keys (see below)
+- **Bugs found:** 2 key mismatch/wrong-key bugs
+
+## Confirmed Unused Keys
+
+### DG.mainPage.* (4 keys)
+
+```
+DG.mainPage.mainPane.versionString
+DG.mainPage.mainPane.versionString.IS_BUILD
+DG.mainPage.mainPane.versionString.SRRI_BUILD
+DG.mainPage.titleBar.saved
+```
+
+### DG.AppController.* (14 keys)
+
+```
+DG.AppController.resetData.title
+DG.AppController.resetData.toolTip
+DG.AppController.resetData.warnMessage
+DG.AppController.resetData.warnDescription
+DG.AppController.resetData.okButtonTitle
+DG.AppController.resetData.cancelButtonTitle
+DG.AppController.optionMenuItems.about
+DG.AppController.optionMenuItems.releaseNotes
+DG.AppController.exportDocument.prompt
+DG.AppController.showWebSiteTitle
+DG.AppController.showAboutTitle
+DG.AppController.showReleaseNotesTitle
+DG.AppController.dropFile.unknownFileType
+DG.AppController.validateDocument.invalidDocument
+```
+
+### DG.DocumentController.* (2 keys)
+
+```
+DG.DocumentController.caseTableTitle
+DG.DocumentController.sliderTitle
+```
+
+### DG.Document.* (1 key)
+
+```
+DG.Document.documentName.toolTip
+```
+
+### DG.CaseCard.* (1 key)
+
+```
+DG.CaseCard.indexString
+```
+
+### DG.Undo/Redo toggle keys (8 keys)
+
+These undo/redo strings exist in `en-US.json` but nothing in the codebase constructs these key names. The corresponding menu items use `DG.DataDisplayMenu.enableNumberToggle` etc., but no undo/redo action references these strings.
+
+```
+DG.Undo.enableNumberToggle
+DG.Redo.enableNumberToggle
+DG.Undo.disableNumberToggle
+DG.Redo.disableNumberToggle
+DG.Undo.enableMeasuresForSelection
+DG.Redo.enableMeasuresForSelection
+DG.Undo.disableMeasuresForSelection
+DG.Redo.disableMeasuresForSelection
+```
+
+### DG.DataContext.* (2 keys)
+
+```
+DG.DataContext.collapsedRowString
+DG.DataContext.noData
+```
+
+### DG.CollectionClient.* (2 keys)
+
+```
+DG.CollectionClient.cantEditFormulaErrorMsg
+DG.CollectionClient.cantEditFormulaErrorDesc
+```
+
+### DG.Utilities.date.* (3 keys)
+
+```
+DG.Utilities.date.localDatePattern
+DG.Utilities.date.timePattern
+DG.Utilities.date.iso8601Pattern
+```
+
+### DG.TableController.* (7 keys)
+
+```
+DG.TableController.newAttrDlg.defaultAttrName
+DG.TableController.renameAttributeInvalidMsg
+DG.TableController.renameAttributeInvalidDesc
+DG.TableController.renameAttributeDuplicateMsg
+DG.TableController.renameAttributeDuplicateDesc
+DG.TableController.setScoreDlg.applyTooltip
+DG.TableController.setScoreDlg.formulaHint
+```
+
+### DG.AttributeFormat.DatePrecision.* (14 keys)
+
+These date format pattern strings exist in `en-US.json` and all locale files, but no code in `apps/dg/` references them (not even dynamically). They may be vestigial from a removed date formatting feature.
+
+```
+DG.AttributeFormat.DatePrecision.year
+DG.AttributeFormat.DatePrecision.month
+DG.AttributeFormat.DatePrecision.day
+DG.AttributeFormat.DatePrecision.hour
+DG.AttributeFormat.DatePrecision.minute
+DG.AttributeFormat.DatePrecision.second
+DG.AttributeFormat.DatePrecision.millisecond
+DG.AttributeFormat.DatePrecisionShort.year
+DG.AttributeFormat.DatePrecisionShort.month
+DG.AttributeFormat.DatePrecisionShort.day
+DG.AttributeFormat.DatePrecisionShort.hour
+DG.AttributeFormat.DatePrecisionShort.minute
+DG.AttributeFormat.DatePrecisionShort.second
+DG.AttributeFormat.DatePrecisionShort.millisecond
+```
+
+### DG.DataDisplayModel.* (3 keys)
+
+```
+DG.DataDisplayModel.rescaleToData
+DG.DataDisplayModel.ShowConnectingLine
+DG.DataDisplayModel.HideConnectingLine
+```
+
+### DG.PlotModel.* (3 keys)
+
+```
+DG.PlotModel.mixup
+DG.PlotModel.showCount
+DG.PlotModel.hideCount
+```
+
+### DG.HistogramView.* (2 keys)
+
+```
+DG.HistogramView.barTipPlural
+DG.HistogramView.barTipSingular
+```
+
+### DG.PlottedAverageAdornment.* (2 keys)
+
+```
+DG.PlottedAverageAdornment.iqrValueTitle
+DG.PlottedAverageAdornment.boxPlotTitle
+```
+
+### DG.GraphView.* (1 key)
+
+```
+DG.GraphView.rescale
+```
+
+### DG.MapView.* (4 keys)
+
+```
+DG.MapView.showGrid
+DG.MapView.hideGrid
+DG.MapView.showPoints
+DG.MapView.hidePoints
+```
+
+### DG.Inspector.* (4 keys)
+
+```
+DG.Inspector.transparency
+DG.Inspector.deleteDataSet
+DG.Inspector.graphMovableValue
+DG.Inspector.graphPlottedIQR
+```
+
+### DG.GameController.* (1 key)
+
+```
+DG.GameController.continuityError
+```
+
+### DG.Locale.name.* (13 keys)
+
+No code in `apps/dg/` constructs or references these locale name keys.
+
+```
+DG.Locale.name.de
+DG.Locale.name.el
+DG.Locale.name.en
+DG.Locale.name.es
+DG.Locale.name.he
+DG.Locale.name.ja
+DG.Locale.name.ko
+DG.Locale.name.nb
+DG.Locale.name.nn
+DG.Locale.name.pl
+DG.Locale.name.tr
+DG.Locale.name.zh
+DG.Locale.name.zh-Hans
+```
+
+## Bugs Found
+
+### 1. Wrong redo key for resizeColumn
+
+**File:** `apps/dg/components/case_table/case_table_controller.js:901-903`
+
+```js
+name: 'caseTable.resizeColumn',
+undoString: 'DG.Undo.caseTable.resizeColumn',
+redoString: 'DG.Undo.caseTable.resizeColumn',  // BUG: should be DG.Redo.caseTable.resizeColumn
+```
+
+The redo action displays the undo string instead of the redo string.
+
+### 2. Key mismatch for componentTitleChange
+
+**File:** `apps/dg/views/component_view.js:292-293`
+
+```js
+undoString: 'DG.Undo.componentTitleChange',
+redoString: 'DG.Redo.componentTitleChange',
+```
+
+**File:** `lang/strings/en-US.json:468-469`
+
+```json
+"DG.Undo.component.componentTitleChange": "Undo changing the component title",
+"DG.Redo.component.componentTitleChange": "Redo changing the component title",
+```
+
+The code references `DG.Undo.componentTitleChange` but the string file defines `DG.Undo.component.componentTitleChange` (with extra `.component.` segment). The undo/redo strings for component title changes are never displayed. Fix either the code or the string keys to match.
+
+## Notes
+
+- Dynamic key construction patterns verified: `DG.PlotBackgroundView.msg` + i (msg0-msg5), `DG.AxisView.` + suffix, `DG.CaseTable.attribute.type.` + type, `DG.DataDisplayMenu.` + item, `DG.Undo/Redo.graph.` + op, `DG.Undo/Redo.map.` + op, `DG.Undo/Redo.toggleComponent.` + action
+- `DG.plugin.*` keys (212 total) are intentionally excluded — they are consumed by plugin code in separate repositories (codap-data-interactives, story-builder, etc.)