Since mid-to-late February 2017, the Google Plus app wouldn't work any longer in my phone, which runs on Android 2.3.6 Gingerbread, and can't be upgraded to a newer Android version.
While the Google Plus website still works on the mobile web, the stock web browser ("Internet") is far too outdated to visit Google+ and other modern sites.
The solution — or workaround, if you will — is to download and install Firefox for Android. Try from Google Play Store first. If that doesn't work, you need to download Firefox from the Mozilla archive.
• Temporarily switch on third-party app installs.
• Below is a breakdown of which Firefox version is compatible with which combination of ARM CPU architecture and older Android version. Each Firefox version links to the appropriate Mozilla archive directory.
- ARMv6 devices —
- Android 2.2, 2.3: Firefox 31.3.0esr
- ARMv7 devices —
- Android 2.2: Firefox 31.0
- Android 2.3 (on a slower phone, <1 GHz): 44.0.2
- Android 2.3: Firefox 47.0