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LimeSurvey version: 6.17 and 7.6
Own server or LimeSurvey Cloud: own server
Survey theme/template: irrelevant
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Hello, 
I have Limesurvey 7.6 installed on a test server and I'm currently checking whether it is suitable to be introduced to our production server. I am wondering what should I test. I have obviously seen this topic: forums.limesurvey.org/forum/installation...s-migration?start=15 and this site: survey-consulting.com/limesurvey-7-migration/ and I either followed or plan to follow their recommendations.

Still I would like to round up as many issues/weird things in general as possible before deciding. Is there anything nonstandard or not mentioned in that article that I should keep in mind?

So far I've come up with:
- testing the way answers are saved - particularly weird date with anonymous surveys ( forums.limesurvey.org/forum/german-forum/159584-zeitstempel )
- potential api connection issues with limonaid
- issues with custom twig files, in my case register_form

Is there anything else worth checking that you can think of or that you know you've already encountered issues with?

joannahawrysz wrote:

So far I've come up with:
- testing the way answers are saved - particularly weird date with anonymous surveys ( forums.limesurvey.org/forum/german-forum/159584-zeitstempel )

There is nothing weird or wrong with the way the date is stored in anonymous surveys. This is the standard behaviour. It is a feature and it  works like this as far as I can remember. Anonymous mode stores a default date to keep the responses anonymous.

- potential api connection issues with limonaid
- issues with custom twig files, in my case register_form

Is there anything else worth checking that you can think of or that you know you've already encountered issues with?

I would mainly test all my important surveys that I would to run unter LS 7.x. Go through it, as people to test them and check how the information is stored.

Special focus I would put on templates, if you use custom templates.

There is nothing weird or wrong with the way the date is stored in anonymous surveys. This is the standard behaviour. It is a feature and it  works like this as far as I can remember. Anonymous mode stores a default date to keep the responses anonymous.

Fair point here, I was a bit imprecise. In previous versions (up to 6.17 I believe) the answer table stored the actual real submit date even for anonymous surveys. It is not crucial, however I do on occasion analyze the surveys by date, especially to know if the reminders I sent were effective. Could be solved by not anonymous surveys though.

I would mainly test all my important surveys that I would to run unter LS 7.x. Go through it, as people to test them and check how the information is stored. 

Great point! I do have some continuous surveys I will add thorough testing of those!

Special focus I would put on templates, if you use custom templates.

Again great call, here I feel mostly safe since I already checked and also had to rebuild all of the themes when version 6 came out, so they're fairly up to date. What I did notice was that my config file for vanilla had missing "<" in exactly 1 line which messed up the themes. Probably a local and not a general problem though.

joannahawrysz wrote:

Fair point here, I was a bit imprecise. In previous versions (up to 6.17 I believe) the answer table stored the actual real submit date even for anonymous surveys. It is not crucial, however I do on occasion analyze the surveys by date, especially to know if the reminders I sent were effective. Could be solved by not anonymous surveys though.

Either you remember wrong or there was a serious bug. One of the characteristics of anonymous surveys is that the date will not be stored.

This hasn't changed since I know Limesurvey, which was somewhere in the LS 1.x area at the beginning of the 2000s. 

www.limesurvey.org/manual/Participant_settings

Citing here the manual:
"This option allows you to determine whether responses to your survey are matched up with information from your survey participants table, or kept "anonymous". The default is "No". If you choose "Yes", then your survey is set to anonymize responses - there will be no way to connect answers and participants. Even the admin will not be able to link response data and participant data. However, you will always be able to specifically view each response entered by your participants in the survey. Thus individual and anonymous analyses can still be done.
Attention: If this feature is activated, the response submission date and the token completed date are always set to 1980-01-01 00:00, no matter of other settings. Invalidating the submission date ensures no match with webserver logs where the token key might show up when a survey is started. Invalidating the token completed date guarantees that you can't align the order of submitted responses to the order of the token date/time."

This is standard behaviour since ever. So if in your case a anonymous survey really stored the time, then this was a bug, in my opinion.