One year later and now with OTA-11 installed ...

I bought a so called USB power meter and run the test below. In summary the ALTOIDS with two AA batteries of 2700mAh each charges the BQ E4.5 to nearly 40%:

LogiLink PA0067
https://www.reichelt.de/usb-messgeraet-5-v-4000-ma-usb-logilink-pa0067-p145269.html

charging test with ALTOIDS "powerbank"

time   LogiLink         BQ E4.5 battery display
14:45  4.55V / 0.12A    44% ALTOIDS connected
14:50  4.58V / 0.19A    49%
14:55  4.59V / 0.21A    50%
15:10  4.62V / 0.27A    57%
15:15  4.62V / 0.30A    60%
15:20  4.62V / 0.29A    63%
15:25  4.63V / 0.31A    65%
15:30  4.63V / 0.32A    67%
15:35  4.64V / 0.32A    68%
15:40  4.63V / 0.32A    70%
15:45  4.63V / 0.32A    71%

~ 1h * 4.6 * 0.3 = 1380mAh

15:50  4.63V / 0.32A    72%
15:55  4.63V / 0.31A    73%
16:00  4.63V / 0.31A    74% ALTOIDS disconnected

(break)

18:20  4.60V / 0.25A    41% ALTOIDS reconnected
18:25  4.57V / 0.20A    45%
18:30  4.56V / 0.17A    47%
18:35  4.56V / 0.14A    49%
18:40  4.54V / 0.09A    50%
18:45  4.54V / 0.07A    50%
18:48  4.52V / 0.00A    50%

~ 0.5h * 4.55 * 0.15 = 340mAh

Normally vim has some encrypt feature to store the resulting file only readable with some key provided:

$ vim -x testfile
Warning: Using a weak encryption method; see :help 'cm'
Enter encryption key: ***
Enter same key again: ***
...
$ file testfile  
testfile: Vim encrypted file data

The vi in our UBT (which is also a vim) does not have this feature compiled in. The flag -x is unknown as it says.

Why?

Today I faced a complete drain of the battery. When I attached the system to power again, I could see that the morph exhausted the memory:

After killing it all was fine. The device (E4.5 latest OTA) was suspended, at least the UI, all the day until I encountered the nearly power off due to lack of energy. Very dangerous.

Magically both, the old Canonical tg app and tg-cli, started working again downloading files and photos. Don't know why, but they do work again. Fine.

Thanks. I always liked these stickers, more than these stupid emoji "I like it", compare here both:

The old (Canonical) tg app had so called stickers, see an example below. I'm missing them in the TELEport app. Any chance to copy them over, even by hand in the file system?

@hummlbach Well, in the case of my wife who had no other subcription to tg as from her old UBphone (OTA-15) tg: I updated her device this morning to UPports and after hours of problems I tried subscribe her phone number with TELEports and it said the code was sent to her tg ... I ended up creating her phone number as account in my business iPhone, the tg server sent a SMS to her number and all was fine.

Forgot: Hours later she complained about the missing stickers in TELEport and I installed her again the old tg client in UBports and was asked if I want to have the code via being called or via tg.

@hummlbach I don't think so. The tg client on my business iPhone let me choose between code by tg or SMS. The old (now unsupported) UT tg client let me even choose for being called (though never used this).

(Deleted the sticker question here and moved it to a better new place.)

After the update of the phone of my wife, she needed to re-subscribe to her tg account, but there is no option to receive the login code by another way than tg itself. Do we missed something?

After the last error with the dev channel I removed all .cache/ubports directory (so the installer must re download all files of the image, and was successfully with the 0.4.1 installer.

Thanks for the provided hints. I will update another E4.5 starting again with the 0.4.5 and will report here.