Codex Theme Import Troubleshooting

Most DexThemes import failures come from an incomplete clipboard value, stopping at general Settings instead of opening Appearance, importing the wrong variant, or using a hand-edited code-theme identifier. Start by copying the theme again and repeating the explicit Appearance import.

DexThemes is community-built and is not affiliated with OpenAI. It validates its current output, but Codex owns the importer. A DexThemes validation result is not proof that a newer or older Codex build accepted and persisted the theme.

Run the clean import sequence

Return to the theme in DexThemes.
Select the intended dark or light variant.
Copy the theme again.
Paste it temporarily into a plain-text editor.
Confirm that it starts with codex-theme-v1: and continues with one complete JSON object.
Copy the untouched string from the editor.
Open Codex Settings.
Choose Appearance manually.
Choose Import theme, paste the string, review it, and choose Import.
Switch Codex to the matching appearance mode and inspect the result.

DexThemes may open general Codex Settings after copying. That is the expected handoff. It does not currently claim a verified direct Appearance deep link or a public route that applies the theme without your approval.

Nothing happened after choosing Copy theme

On desktop, Copy theme copies the theme to your clipboard and then opens Settings. It does not mean that Codex silently applied the payload.

Check the clipboard in a plain-text editor. If the string is present, return to Codex and continue through Appearance and Import theme. If no string is present, the browser may have denied clipboard access. Use the selectable import text when the interface offers it, or copy again after allowing clipboard access for the action you initiated.

Do not edit Codex configuration files as a shortcut. File mutation does not prove the supported import flow worked, and a malformed setting can create a separate problem.

Codex says the theme is invalid

Check these structural requirements:

The prefix is exactly codex-theme-v1:.
The prefix is immediately followed by a JSON object.
There are no outer quotation marks around the complete string.
variant is exactly dark or light.
Required colors are six-digit hex values such as #A1B2C3.
contrast is an integer from 0 through 100.
opaqueWindows is a boolean.
fonts.code and fonts.ui are strings or null.
codeThemeId is a registered family that supports the selected variant.

Use the Codex theme format reference for the exact payload shape. If the string came from DexThemes, recopying is safer than repairing JSON by hand.

The string uses a filename-like code theme ID

The code theme ID is a registered family name, not necessarily a bundled syntax-theme filename. Current DexThemes source canonicalizes known older values:

github-dark-default becomes github for a dark import.
github-light-default becomes github for a light import.
gruvbox-dark-hard becomes gruvbox for a dark import.
one-dark-pro becomes one for a dark import.

New DexThemes strings should already contain the canonical value. Do not replace an ID with a filename found in an application bundle. Recopy the current theme instead.

Only dark or light changed

This is usually expected. Each import string contains only one variant. Select and copy the other variant in DexThemes, then import it into the other Appearance slot.

If the theme offers only one variant, DexThemes cannot manufacture the missing side during installation. Choose another theme with both variants or build the second palette yourself.

The import worked but looks different from the preview

The DexThemes preview is a Codex-like design surface, not a complete emulator. Differences can come from:

The installed Codex version.
The selected base code-theme family.
Operating-system color rendering.
Display brightness and color profile.
Font availability and font rendering.
Appearance states that are not represented in the preview.
Preview-only sidebar or code-background colors that are not separate fields in the current import payload.

Judge the result in the real app. If text, diffs, or controls are hard to read, restore a comfortable built-in theme or adjust the palette. The official Codex settings guide documents Appearance controls for base theme, accent, background, foreground, and fonts.

A requested font did not appear

The import format can carry UI and code font names, but it does not contain font files. A name that is missing, spelled differently, or unavailable on the computer may fall back according to Codex and the operating system.

Open Codex Appearance and choose the font there. Test ordinary text, punctuation, code ligatures, and diff alignment. See Change Codex UI and code fonts for the safer settings-first workflow.

A CLI theme did not import

DexThemes app imports and Codex CLI themes are different systems. A desktop import begins with codex-theme-v1:. A CLI custom theme is a .tmTheme file placed under $CODEX_HOME/themes and selected with /theme, as described in the official CLI customization guide.

Do not paste a .tmTheme file into Codex Appearance, and do not place a codex-theme-v1 string in the CLI themes directory. Read Codex app themes versus CLI themes.

Collect a useful, safe bug report

If a clean recopy still fails, record:

The public theme name and selected variant.
Your Codex version and operating system version.
The exact visible error message.
Whether the prefix and JSON were complete.
Whether the failure happened before or after you approved Import.
Whether a built-in theme can still be selected.

Do not include credentials, account identifiers, private repository names, private URLs, or screenshots containing sensitive work. If you share the payload, verify that it contains only appearance fields first. Report DexThemes issues through the project's public issue tracker, and use Codex feedback channels for importer behavior owned by Codex.