[21.4.3] Error obtaining explain plan - Failed to query plan_table: node has no children

Hello,

Every query i try to get the explain plan using the SQL Developer button always throws the error displayed in the following image:

After clicking OK it displays the plan but without the costs and cardinality:

Tried the same on a new clean copy of SQL Developer but the same error appears.

Obtaining the explain plan by querying the PLAN_TABLE works as expected:

I'm using the latest SQL Developer version - v21.4.3.063

Would appreciate some help.

Regards,

Filipe