The tool 'tmpugCygk#infernal-cmsearch-v1.1.2.cwl' is missing. Cannot build workflow module

[ghost]

When we restart Galaxy (after having edited and saved the workflow),
and we try to edit the wf again, warning below occurs

galaxy.workflow.modules WARNING The tool 'tmpugCygk#infernal-cmsearch-v1.1.2.cwl' is missing. Cannot build workflow module.
galaxy.workflow.modules WARNING The tool 'tmpugCygk#concatenate.cwl' is missing. Cannot build workflow module.
galaxy.workflow.modules WARNING The tool 'tmpugCygk#cmsearch-deoverlap-v0.02.cwl' is missing. Cannot build workflow module.

then the workflow cannot be edited anymore (links and boxes are missing).

It seems to be related by the following change in the database:

Before saving

sqlite> select type,label,tool_id,tool_hash from workflow_step where type='tool' order by label;
tool        cmsearch                7943013e61897f4949e77546edeabd960a2f608067e2ecd523a1d2ef010e9682
tool        concatenat              742a9252f4cf1b80bcb57d20aa4133edbaa46b8a3112a9055110db18b1e446dc
tool        remove_ove              e384c3b53464dbea34880afedfb09f6857ab89313014f76f9eea23e15e1c83b8

After saving

sqlite> select type,label,tool_id,tool_hash from workflow_step where type='tool' order by label;
tool        cmsearch                   7943013e61897f4949e77546edeabd960a2f608067e2ecd523a1d2ef010e9682
tool        cmsearch    tmpkadxtU#inf
tool        concatenat                 742a9252f4cf1b80bcb57d20aa4133edbaa46b8a3112a9055110db18b1e446dc
tool        concatenat  tmpkadxtU#con
tool        remove_ove                 e384c3b53464dbea34880afedfb09f6857ab89313014f76f9eea23e15e1c83b8
tool        remove_ove  tmpkadxtU#cms

(after clicking on 'Save' button in the workflow editor, tools are
referenced using 'tool_id' column instead of 'tool_hash' column (in
'workflow_step' table)).

When hacking the code (link) to force populating 'tool_hash' column and setting 'tool_id' column to NULL, the problem seems to disappear.