For 31 of my preferences, the value returned by mw.user.options.get( ... ) in debug mode¹ is different from its real value in production². Notice both the difference in values and types of the variables!
| Preference | Value in production | Value in debug mode |
|---|---|---|
| 'echo-email-format' | 'plain-text' | 'html' |
| 'echo-subscriptions-email-article-linked' | '1' | false |
| 'echo-subscriptions-email-edit-thank' | '1' | false |
| 'echo-subscriptions-email-edit-user-talk' | 1 | false |
| 'echo-subscriptions-email-mention' | '1' | false |
| 'echo-subscriptions-email-reverted' | '1' | false |
| 'echo-subscriptions-web-flow-discussion' | '' | true |
| extendwatchlist | '1' | 0 |
| fancysig | '1' | 0 |
| 'gadget-WatchlistGreenIndicators' | '' | 1 |
| 'gadget-charinsert' | '' | 1 |
| math | '5' | 0 |
| nickname | '[[User:He7d3r|Helder]]' | '' |
| searchNs1 | '1' | false |
| searchNs10 | '1' | false |
| searchNs11 | '1' | false |
| searchNs12 | '1' | false |
| searchNs13 | '1' | false |
| searchNs14 | '1' | false |
| searchNs15 | '1' | false |
| searchNs2 | '1' | false |
| searchNs3 | '1' | false |
| searchNs4 | '1' | false |
| searchNs5 | '1' | false |
| searchNs8 | '1' | false |
| searchNs828 | '1' | false |
| searchNs829 | '1' | false |
| searchNs9 | '1' | false |
| showhiddencats | '1' | false |
| 'visualeditor-enable' | '1' | 0 |
| 'visualeditor-hidebetawelcome' | '1' | 0 |
| watchdefault | '1' | 0 |
¹ https://en.wikipedia.org/wiki/Special:BlankPage?debug=1
² https://en.wikipedia.org/wiki/Special:BlankPage