Drupal 9 compatibility contribution quickstart guide for Drupal Global Contribution Weekend 2020 | Gábor Hojtsy on Drupal
![Drupal 9 Deprecated Code Report [#3074029] | Drupal.org](https://www.drupal.org/files/issues/2020-04-18/Screenshot%202020-04-18%20at%203.13.44%20PM.png "Drupal 9 Deprecated Code Report [#3074029] | Drupal.org")
Drupal 9 Deprecated Code Report [#3074029] | Drupal.org
![Drupal 9 replace deprecated function drupal_set_message() [#3221131] | Drupal.org](https://www.drupal.org/files/issues/2021-08-23/3221131_before.png "Drupal 9 replace deprecated function drupal_set_message() [#3221131] | Drupal.org")
Drupal 9 replace deprecated function drupal_set_message() [#3221131] | Drupal.org
A preview of the breaking changes in Drupal 9 | QED42
What do you Need to Upgrade from Drupal 9 to Drupal 10?
Drupal 9: Automated Deprecated Code Removal - A Proof of Concept | Pronovix
Drupal 9 to 10 upgrade tools
Anyone Can Help Upgrade Drupal Projects to Be Drupal 9 Compatible!
drupal_set_message() Cheatsheet: Variables, links, and formatting | LevelTen Dallas, TX
Drupal: drupal_set_message for anonymous user - YouTube
Automate Drupal 9 upgrades
![Drupal 9 Compatibility: Fix deprecations [#3198792] | Drupal.org](https://www.drupal.org/files/issues/2021-02-16/Screenshot%202021-02-16%20at%2021.11.14.png "Drupal 9 Compatibility: Fix deprecations [#3198792] | Drupal.org")
Drupal 9 Compatibility: Fix deprecations [#3198792] | Drupal.org
![Drupal 9 compatibility and Remove usage of deprecated drupal_set_message [#3151951] | Drupal.org](https://www.drupal.org/files/issues/2020-06-16/Screen%20Shot%202020-06-16%20at%201.54.06%20PM.png "Drupal 9 compatibility and Remove usage of deprecated drupal_set_message [#3151951] | Drupal.org")
Drupal 9 compatibility and Remove usage of deprecated drupal_set_message [#3151951] | Drupal.org
![Support render arrays for drupal_set_message() [#2505497] | Drupal.org](https://www.drupal.org/files/issues/Uses__attached_in_render_array_with_drupal_set_message_____Site-Install.png "Support render arrays for drupal_set_message() [#2505497] | Drupal.org")
Support render arrays for drupal_set_message() [#2505497] | Drupal.org
Drupal 9 upgrade: preparing your website with the latest tools | WishDesk
Get ready for Drupal 9 | Droptica Blog
![Remove Call to deprecated function drupal_set_message() [#3071530] | Drupal .org](https://www.drupal.org/files/issues/2019-09-29/certigiflatest.gif "Remove Call to deprecated function drupal_set_message() [#3071530] | Drupal .org")
Remove Call to deprecated function drupal_set_message() [#3071530] | Drupal .org
9.8.1. hook_form_alter() add submit and validate for existing form. | Drupal Book
How to prepare your module for Drupal 9 | ADCI Solutions
Site Owner's Guide to a Smooth Drupal 9 Upgrade Experience
Sortie de Drupal 9 et mise à jour depuis Drupal 8 | Actency
How to prepare your module for Drupal 9 | ADCI Solutions
![Drupal 9 replace deprecated function drupal_set_message() [#3221131] | Drupal.org](https://www.drupal.org/files/issues/2021-08-23/3221131_after.png "Drupal 9 replace deprecated function drupal_set_message() [#3221131] | Drupal.org")
Drupal 9 replace deprecated function drupal_set_message() [#3221131] | Drupal.org
![Drupal set message deprecated [#3099387] | Drupal.org](https://www.drupal.org/files/issues/2019-12-09/scmsg_errors.PNG "Drupal set message deprecated [#3099387] | Drupal.org")
Drupal set message deprecated [#3099387] | Drupal.org
![Drupal 9 Deprecated Code Report - functions drupal_set_message(), Unicode::strtolower(), constant DATETIME_DATETIME_STORAGE_FORMAT, and class Drupal\simpletest\WebTestBase [#3130494] | Drupal.org](https://www.drupal.org/files/issues/2020-05-07/DCAT-patch-apply.png "Drupal 9 Deprecated Code Report - functions drupal_set_message(), Unicode::strtolower(), constant DATETIME_DATETIME_STORAGE_FORMAT, and class Drupal\simpletest\WebTestBase [#3130494] | Drupal.org")