Upgrade to London / Kingston from Jakarta , seems stuck while loading plugin "fix_email_utf8.xml"
The script in "fix_email_utf8.xml" applies the fix for the known error as described here>> Four-byte UTF8 emoji characters cause emails text to be truncated when stored in the database . The fix script updates the schema for sys_email and related shard tables , amount of time taken to run the script will depend on the size of the data which is normal.
The fix script updates the schema for sys_email and related shard tables , the amount of time taken will depend on the data on sys_email and related shard tables. While the system is updating the schema the upgrade monitor will show that this script "fix_email_utf8.xml"is running, this is normal behavior and does not indicate that the upgrade is stuck.