pfSense

If you have existing voucher settings, and update a system to master/2.1, the voucher settings will cause some issues, such as:

Fatal error: Cannot create references to/from string offsets nor overloaded objects in /etc/inc/voucher.inc on line 680

If you unset $config['voucher'] then it works again.

Here is the old section of the config:

<voucher>
    <charset>0123456789</charset>
    <rollbits>16</rollbits>
    <ticketbits>7</ticketbits>
    <saveinterval>5</saveinterval>
    <checksumbits>5</checksumbits>
    <magic>4567272</magic>
    <publickey>LS0tLS1CRUdJTiBQVUJMSUMgS0VZLS0tLS0NCk1DQXdEUVlKS29aSWh2Y05BUUVCQlFBRER3QXdEQUlGQU1jOG1ma0NBd0VBQVE9PQ0KLS0tLS1FTkQgUFVCTElDIEtFWS0tLS0tDQo=</publickey>
    <privatekey>LS0tLS1CRUdJTiBSU0EgUFJJVkFURSBLRVktLS0tLQ0KTUNzQ0FRQUNCUURIUEpuNUFnTUJBQUVDQkhrRWlmVUNBd0Q2QndJREFNdi9BZ0lZZndJQ0JiTUNBaUVVDQotLS0tLUVORCBSU0EgUFJJVkFURSBLRVktLS0tLQ==</privatekey>
    <msgnoaccess>Voucher invalid</msgnoaccess>
    <msgexpired>Voucher expired</msgexpired>
    <vouchersyncdbip/>
    <vouchersyncport/>
    <vouchersyncusername/>
    <vouchersyncpass/>
    <roll>
        <number>1</number>
        <minutes>44640</minutes>
        <comment/>
        <count>100</count>
        <used>AAAAAAAAAAAAAAAAAA==</used>
        <active/>
    </roll>
</voucher>

(This is a testing only VM, those vouchers were not in use or important in any way)