Unless you changed the default, this will be 16 MB:

mysql> SHOW VARIABLES WHERE Variable_name="max_allowed_packet";
+--------------------+----------+
| Variable_name      | Value    |
+--------------------+----------+
| max_allowed_packet | 16777216 |
+--------------------+----------+

Rails Long Term Support

Rails LTS provides security patches for old versions of Ruby on Rails (2.3, 3.2, 4.2 and 5.2)

• Prevents you from data breaches and liability risks
• Upgrade at your own pace
• Works with modern Rubies

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