Quick start

We assume you have composer-based TYPO3 installation with extension EXT:gridelments (gridelementsteam/gridelements) installed.

Make Backups or work on a development system

Warning

Create a backup of your database and filesystem before applying these steps. It is highly recommended to use this extension on a development system only.
Install EXT:container
```
composer req b13/container
```
Copied!
Keep EXT:gridelements installed for now.
Install EXT:gridtocontainer
```
composer req --dev sbublies/gridtocontainer
```
Copied!
See the chapter on Installation. Make sure the TypoScript template is included. We install the extension as a dev-requirement as it should not be used on productive systems.
Check which of the available grid elements are in use

Go to the module Admin tools > Grid migration provided by this extension. See also What grid elements do i have on my site?.
Create alternative containers for each grid element

See the EXT:container documentation.
Migrate all grid elements to containers

Using the module Admin tools > Grid migration migrate all grid elements to the respective containers. See also Migrate grid elements from gridelements layout key.
Optional: Migrate FlexForm content

If your grid elements used FlexForms you have to migrate the values stored in the FlexForms by other means. See chapter Known problems.
Check the migration

Is everything being displayed as expected in frontend and backend?
Remove EXT:gridelements and this extension

Remove or replace all extensions that require EXT:gridelements and remove the requirement from your sitepackage. Then remove EXT:gridelements. You can also remove EXT:gridtocontainer after successfully migrating all containers:
```
composer remove gridelementsteam/gridelements sbublies/gridtocontainer
```
Copied!
Clean up the database

Search in the database for content elements that still use the colpos -1 and resolve them. See chapter Clean up the database for details.
Make a database compare

Got to Admin tools > Maintenance > Analyze Database and undo all changes that EXT:gridelements made to your database.