Memory leak in Mac Proxy detection when a PAC file is used

Whenever QNetworkProxyFactory::systemProxyForQuery is called on MacOS a memory leak occurs. This can be easily tested with the attached sample application and running it with  leaks --atExit this results in following leak report:

Querying proxy for https://www.qt.io/adfsda
{{ Query returned 1 proxies}}
{{ {{ Type: HttpProxy Proxy: 192.168.50.153:3128 (Credentials: }}}}
{{ Process: proxy_test [38800]}}
{{ Path: /Users/USER/*/proxy_test}}
{{ Load Address: 0x10418b000}}
{{ Identifier: proxy_test}}
{{ Version: ???}}
{{ Code Type: X86-64}}
{{ Parent Process: leaks [38799]Date/Time: 2019-10-24 16:15:16.920 +0200}}
{{ Launch Time: 2019-10-24 16:15:16.797 +0200}}
{{ OS Version: Mac OS X 10.14.6 (18G103)}}
{{ Report Version: 7}}
{{ Analysis Tool: /usr/bin/leaksPhysical footprint: 1624K}}
{{ Physical footprint (peak): 1624K}}
{{ ----leaks Report Version: 4.0}}
{{ Process 38800: 1274 nodes malloced for 273 KB}}
{{ Process 38800: 12 leaks for 864 total leaked bytes.12 (864 bytes) ROOT LEAK: <CFDictionary 0x7fb0a2c014c0> [64] item count: 7}}
{{ {{ 8 (592 bytes) <CFDictionary (Value Storage) 0x7fb0a2c013b0> [112]}}}}
{{ {{ 6 (416 bytes) <CFDictionary 0x7fb0a2c00a20> [64] item count: 1}}}}
{{ {{ 4 (320 bytes) <CFDictionary (Value Storage) 0x7fb0a2c01320> [32]}}}}
{{ {{ 3 (288 bytes) <CFDictionary 0x7fb0a2c00e50> [64] item count: 6}}}}
{{ {{ 1 (112 bytes) <CFDictionary (Key Storage) 0x7fb0a2c00de0> [112]}}}}
{{ {{ 1 (112 bytes) <CFDictionary (Value Storage) 0x7fb0a2c01500> [112]}}}}
{{ {{ 1 (32 bytes) <CFDictionary (Key Storage) 0x7fb0a2c00a60> [32]}}}}
{{ {{ 1 (64 bytes) <CFArray 0x7fb0a2c00ae0> [64] item count: 2}}}}
{{ {{ 3 (208 bytes) <CFDictionary (Key Storage) 0x7fb0a2c01420> [112]}}}}
{{ {{ 1 (48 bytes) <CFString 0x7fb0a2c01590> [48] length: 21 "ProxyAutoConfigEnable"}}}}
{{

Unknown macro: { Unknown macro}

}}}

Note: this only happens if the system proxy settings have automatic proxy configuration enabled using a .pac file!