What are the pros and cons of CodeIgniter 3 compared to Yii 2?

Question

CodeIgniter

I plan to move to a new job in the near future. In the old place, we used Yii with might and main, especially the 2nd branch. The experience I got was very significant. At the new place, all projects are not written in CodeIngniter (I have not worked with it at all yet), but I was told that I can write new ones in whatever I want.
Accordingly, I wonder how they differ in practice, especially in terms of high loads? Yii 2 is definitely more modern, but CodeIgniter is not dead at all - the last update was in December 2017. At the new place of work, projects with much higher attendance than at the old one, because they work for the CIS as a whole, and not for the regional market.

Answer 1

CodeIgniter, of course, is worth learning, since in a new place all old projects are written on it, but since you have good knowledge of Yii2, then you should not change it.
Chasing fashion or not is everyone's business.
Personally, I prefer Yii2.

Answer 2

Unfortunately, we either write joys at work in symphony, but for any other projects I prefer AI2.
As the speaker above, I will not consider him dead. Plus, chasing the mainstream is a pointless undertaking, as an example, the same ever-changing trends of the fronts.

Answer 3

Accordingly, I wonder how they differ in practice, especially in terms of high loads?

Neither one nor the other is used in projects with high loads.