1) Every new edition (version) of a programming platform or any other area will certainly have many internal modifications that are not detailed for the general public. Thus, it is prudent to always be aware that this normally always happens.
2) knowing the number one tip, it is always indicated, at least in the case of RAD Studio (Embarcadero) in particular, when migrating from one edition to another, no matter if it is smaller or larger, to create the essential and primary files of the programming language. In this case, create a new project and add the old files. In this way, you will ensure that at least the files needed to compile and run the project conform to the new edition (version). This happens with many other programming languages, or even common day-to-day software.
3) RAD Studio creates several files necessary to compile and run a new user application, so many default settings are inserted in these files, so that the project can meet the new needs of the new language edition. For example, the files "*.DPROJ", "*.RES", "Androis.Manifest.xml", etc... Most compilation problems, or even opening the file, can occur at this point.
4) To try to fix the essential part of a project that will be opened, compiled and executed in another edition of the language, it is always wise to create at least the project file (in the case of RAD Studio, *.DPR, *. PROJ, *.RES, etc... directly in the new IDE, and add the other files to this new project, so you can have several project files, one for each IDE you want to use.
Even the tip of creating a new project file in the new IDE used, and then adding the old files to the project, is indicated by Embarcadero itself.
An example of incompatibility, for example, a file "Android.Manifest.xml" from version Android 5 and version Android 11. A lot has changed since the old version, hasn't it?
In the case of projects for Mobile, Android in particular, it is often necessary to update the "*.jar" files that are referenced in the original project file, otherwise the project may not even be compiled.
Did you understand?
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The higher the degree, the greater the respect given to the humblest!RAD 11.3