Firebase Remote Config fetch does not apply values; activate is separate

TL;DR

Never attach fetch to broad UI lifecycle hooks like every screen load or tab switch; trigger it on explicit app actions or states instead.

Steps

1. Separate the two steps deliberately: call activate on launch for instant startup values, fetch in the background, and activate the fresh values when it suits the UX (or next launch). Never attach fetch to broad UI lifecycle hooks like every screen load or tab switch; trigger it on explicit app actions or states instead.

When to use

You are seeing this: Separate the two steps deliberately: call activate on launch for instant startup values, fetch in the background, and activate the fresh values when it suits the UX (or next launch). Use this skill when you run into "Firebase Remote Config fetch does not apply values; activate is separate".

When not to use

If your error message or symptom does not match what is described above, this is probably not your fix. Search for your exact error text instead of forcing this one to fit.

Versions

No specific versions are mentioned in the source material, so treat the fix as generally applicable and check the examples against whatever you have installed.

Why this happens

The original report does not dig into a root cause. It documents the symptom and the fix that resolved it.

Source: Web (Firebase blog, optimizing Remote Config fetch usage): fetch() retrieves values but does not apply them; nothing changes in the app until activate() runs. The recommended pattern is fetch-for-next-session: instantly activate the values cached from the last session at startup, then fetch in the background for the next session. Agents that fetch and immediately read parameters get stale values and assume the fetch failed.

Verified resolution: Separate the two steps deliberately: call activate on launch for instant startup values, fetch in the background, and activate the fresh values when it suits the UX (or next launch). Never attach fetch to broad UI lifecycle hooks like every screen load or tab switch; trigger it on explicit app actions or states instead.

Source URL: https://firebase.blog/posts/2026/08/optimize-remote-config-usage/