Xiaomi’s Redmi 9 lineup is famous for its flexibility in customizing the look, but over time, the abundance of installed designs can lead to a slowdown or overflow of the system partition. Users often face the need to return the original look to the system or simply make room by removing unnecessary design files. This process is not always obvious, since the standard menu does not always offer a direct “Delete” button for all elements at once.
In this article, we will take a look at all the available ways to clean up the theme storage, including working through the standard Themes app, manual file deletion, and even radical reset methods. You will learn how to distinguish system files from user downloads without disrupting the stability of the MIUI operating system.
Why do you delete topics and how much damage they do to the system?
Many users see themes as a harmless way to personalize, without thinking that each one takes up space in internal memory. Theme files contain not only wallpaper images, but also graphics of system icons, fonts, notification sounds and animation scripts. The accumulation of dozens of such packages can significantly reduce the available space, which is critical for models with 64 GB of memory or less.
In addition, poorly optimized third-party themes can cause the Launcher desktop to slow down and increase RAM consumption in the background. System resources are spent on indexing new graphics elements, which is especially noticeable on budget processors. Removing unused content is the first step to optimize performance.
Also, consider that some themes may contain advertising modules or incorrect paths to system files, leading to errors in the interface, and regular cleaning allows you to maintain the “hygiene” of the software and avoid conflicts between different versions of the same design elements.
⚠️ Note: Removing the active theme that is currently applied to the system may cause the interface to temporarily reset to a standard view before the device restarts.
It's important to understand the difference between a theme that's just downloaded and one that's currently active: an active theme is loaded into RAM and is actively used by the processor to render items. If you plan to remove the active packet, the system will automatically switch to defaulting on Classic or Default.
Removing themes through the standard “Themes” app
The safest and most recommended way to manage your design is to use a built-in tool from Xiaomi. Themes is pre-installed on all devices with a MIUI shell and provides full access to the library of downloaded files. To start work, you need to launch the application and go to the user profile.
At the bottom of the screen, look for a person icon or Profile, which stores your entire download history. The interface may vary slightly depending on the version of MIUI, but the logic remains the same: all downloaded themes are divided into categories "Buyed", "Downloaded" and "Offline", and we are interested in the tab with the downloaded files.
To remove, click on the icon of a particular theme to open its detailed description. In the upper right corner or at the bottom of the screen, a button with the image of the trash can or the item "Delete" will appear. Confirm the action in the pop-up window. This method ensures that only user data will be deleted, and system files will remain intact.
If you want to delete multiple themes at once, some versions of the app have a mass control feature: press and hold your finger on one of the thumbnails, after which you will see checkboxes for selection. Packet removal saves a lot of time if you need to clear the memory from a dozen old designs.
☑️ Pre-deletion check
It is worth noting that some themes may be protected from deletion if they are part of promotions or a pre-installed package. In such cases, the delete button may be missing or inactive.
Manual cleaning through the file manager
For advanced users who don’t have the standard functionality, manual file deletion is available, and this requires caution because it works directly with the Android file structure, and you’ll need a standard Explorer or a more powerful analog, such as MI File Manager or Total Commander.
Theme files are usually located in hidden system directories. To access them, you need to enable hidden files in your Explorer settings. The path to these topics is most often as follows: MIUI/theme or Android/data/com.android.thememanager/files. The exact path depends on the Android version and the specific MIUI build.
Inside the folder, you'll see files with the.mtz extension or folder sets with obscure names, which are theme packages. Before deleting any file, you're strongly encouraged to remember its name or take a screenshot of the folder's contents. System themes often have short names or titles like default, classic, mi_global — They can't be touched.
/storage/emulated/0/MIUI/theme/After highlighting unnecessary files, press the delete button. The system may request permission confirmation as you are trying to change the data in the protected area. After cleaning the folder, it is recommended to restart the smartphone so that the system recalculates the file index and frees up space in the file system table.
What to do if the files are not deleted?
The advantage of the manual method is that it allows you to find and remove "tails" - remnants of previously deleted themes that for some reason remained in memory, these can be cached images or temporary files that the standard interface does not show.
Resetting theme to factory settings
If your goal is not just to make room, but to return the phone to its original, clean look, as it did right after you bought it, then the best solution is to completely reset the theme, which will bring all icons, wallpaper, fonts and sounds of system events back to their default state, and this often helps solve problems with the "glutty" interface.
To reset, open the Themes app and go to your profile. In the upper right corner, find the settings icon (cogs). In the menu that opens, select Reset theme or Restore the Default Theme. The system will alert you that all changes will be canceled.
This process doesn't delete your personal photos, contacts or installed apps; it only affects the visual shell; once reset, the desktop may look unusual: icons will stand in standard places, and widgets can disappear from the lock screen. This is normal behavior.
| Parameter | Before dumping. | After discharge |
|---|---|---|
| Desktop wallpaper | Customized | Standard MIUI |
| Application icons | Stylized | Original. |
| Fonts of the system | Castomy | Roboto/Standard |
| Notification sounds | From the subject | Systemic |
It is important to note that the theme reset does not delete the theme files themselves from the phone's memory; it only cancels their use. To completely dispose of the files, after the reset, you still need to perform the deletion procedure through the profile or file manager, as described in the previous sections.
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After resetting the theme, it is recommended to restart the device so that all graphic elements are correctly redrawn and the system cache is updated.
Removal of fonts and design components
Often, users install custom fonts and lock screen components along with themes, which also take up space and can affect text readability or interface speed, and are managed in the same Themes app but in separate tabs.
Go to your profile and select the Fonts tab, and here you will see a list of all the fonts installed. The active font is marked with the appropriate icon. To remove the third-party font, click on it and select the Delete button. You can return the standard font by selecting the Roboto or MI Sans font in the directory and applying it.
The Lock screen tab (or Always Screen on) contains loaded plugins. Some of them can be quite heavy and consume battery power. Removing unused lock styles is a good way to extend the battery life of the Redmi 9.
Care should be taken when removing system components. If you see a font or element that is called "System" or has no explicit author, it is better to leave it.
⚠️ Warning: Removing the active font without first selecting another one can cause the text in the menu to become unreadable or turn into squares before rebooting.
In some cases, after deleting fonts, the Theme process in application settings is forced to stop so that the changes take effect immediately, without which the system can continue to use the old font cached data.
Problem Solving: If Topics Are Not Deleted
Xiaomi users sometimes encounter a situation where the theme “hangs” during the deletion process or the delete button is inactive.This can be caused by an error in the Themes app or a conflict of MIUI versions. The first step should always be to clear the cache of the theme app itself.
Go to Settings → Apps → All Apps → Topics. Select Memory and click Clear Cache (not data, specifically cache). This won’t delete your themes, but will reset temporary files that may block deletion. After that, try deleting the theme again.
If that didn't help, check for updates for the Themes app through the GetApps store or Google Play. An outdated version of the app may not work properly with new theme formats or have bugs in the file manager. Xiaomi regularly releases patches for its system applications.
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If standard methods don’t work, try removing the theme in Safe Mode, where third-party processes don’t interfere with the system.
As a last resort, if the theme file is corrupted and not deleted in any way, you can use the connection to the computer. Connect the phone to USB in file transfer mode (MTP) and try to delete the theme file through the computer file system. PC access rights often ignore some software locks Android.
It is also worth checking whether the “Block Themes” feature is enabled in your Mi Account settings if you are using a family or corporate profile, in which cases deletion may be prohibited by security policy.