Chrome not Firefox are not dumping to SSLKEYLOGFILE variable
You are doing something wrong. Tested on version 58 & you do not need to reboot. To activate either:
- set environment variable e.g.
SSLKEYLOGFILEto%USERPROFILE%\sslkeysENV.pms - run chrome with argument e.g.:
"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" --ssl-key-log-file=%USERPROFILE%\sslkeysARG.pms
With Firefox the features seems to be disabled by default and is only available in debug builds. With Chrome this might have been vanished by switching the underlying SSL engine from NSS (which implemented this feature and is also used in Firefox) to BoringSSL (which maybe does not have this feature).
Update: according to @Lekensteyn (see comment) the feature is again available in current Firefox and Chrome builds.
Try Firefox Developer edition, the above mentioned feature is turned on by default. I tested yesterday only.