Keyman Developer testing page (Web and Mobile Targets) - keymanapp/keyman GitHub Wiki
From the .kmn tab --> Build --> Test Keyboard on web --> Open in browser
From the .kps tab --> Build --> Test package on web --> Open in browser
From the file browser:
Navigate to [user]/AppData/Roaming/Keyman/Keyman Developer/Server
--> rm cache/ and cache.json
cd /c/Program Files (x86)/Keyman/Keyman Developer
node server