[Lazarus] Installed lazarus-ide in Ubuntu18, cannot install package

[Juha Manninen]

On Wed, Oct 24, 2018 at 10:16 PM Brian via Lazarus
<lazarus at lists.lazarus-ide.org> wrote:
> Maybe not, but my point is that I was running the 1.8.4 .DEBs from
> SourceForge with no problems.

Yes but you are confusing unrelated things now.
You were running Lazarus 1.8.4 with no problems because it had only
deprecated ValidUTF8String instead of removing it.
Using .deb packages was irrelevant. Getting sources for 1.8.4 through
SVN would work equally well.
This was in 1.8.4 :
 function ValidUTF8String(const s: String): String; inline; deprecated
'Use Utf8EscapeControlChars() instead.';
So the solution is to use Utf8EscapeControlChars() in IBCustomDataSet,
whoever maintains it.

Juha